#the-open-journal-of-astrophysics — Public Fediverse posts

Lá Saoire i mí Dheireadh Fómhair

Today being the last Monday of October, it’s a Bank Holiday here in Ireland – Lá Saoire i Mí Dheireadh Fómhair (literally, the Holiday at the End of the Month of October) so I had the morning off; I have a telecon this afternoon. This week is Study Week too so there are no lectures or tutorials until next Monday, when we resume for the seven remaing weeks of the Semester.

I’ll be travelling tomorrow to give a seminar at Queen’s University Belfast. My talk will have the title Open Access Publishing in Astrophysics and the Open Journal of Astrophysics, an updated version of a talk I’ve given in a number of places. over the past few years. I was looking at NASA/ADS just now to get the latest statistics and discovered that articles in the Open Journal of Astrophysics have now received over 10,000 citations at an average of 14.9 per paper. The average has been consistent since the first few years of publishing, which is interesting for the reason that our publishing rate is rising steadily so that most of our publications are very recent.

Anyway, I’m quite looking forward to the trip. The worst of the awful weather of the past few days seems to have passed and I hope I can make it to and from Belfast by train without the intervention of floods or fallen trees.

Another name for the present Bank Holiday is Lá Saoire Oíche Shamhna (Halloween Holiday), although Halloween itself does not occur until Saturday. I’ll be travelling again at the weekend, but this time purely for pleasure.

At this time of year many of the buildings of the historic South Campus are ablaze with Red Virginia Creeper:

It’s very pretty, but not good for the brickwork!

(Another) Call for Editors at the Open Journal of Astrophysics!

The number of papers being submitted to the Open Journal of Astrophysics continues to rise, as demonstrated by the following graphic which shows the stats for new submissions for the last five years:

It’s very clear that the thicket is getting thicker and thicker as times goes on! The increasing number of articles is of course very welcome indeed, but it is increasing the load on our Editorial Board and that includes me! I think it’s time once again to look for more volunteers to join the team, in any area of astrophysics. As a reminder, here are the areas we cover, corresponding to the sections of astro-ph on the arXiv:

1. astro-ph.GA – Astrophysics of Galaxies. Phenomena pertaining to galaxies or the Milky Way. Star clusters, HII regions and planetary nebulae, the interstellar medium, atomic and molecular clouds, dust. Stellar populations. Galactic structure, formation, dynamics. Galactic nuclei, bulges, disks, halo. Active Galactic Nuclei, supermassive black holes, quasars. Gravitational lens systems. The Milky Way and its contents
2. astro-ph.CO – Cosmology and Nongalactic Astrophysics. Phenomenology of early universe, cosmic microwave background, cosmological parameters, primordial element abundances, extragalactic distance scale, large-scale structure of the universe. Groups, superclusters, voids, intergalactic medium. Particle astrophysics: dark energy, dark matter, baryogenesis, leptogenesis, inflationary models, reheating, monopoles, WIMPs, cosmic strings, primordial black holes, cosmological gravitational radiation
3. astro-ph.EP – Earth and Planetary Astrophysics. Interplanetary medium, planetary physics, planetary astrobiology, extrasolar planets, comets, asteroids, meteorites. Structure and formation of the solar system
4. astro-ph.HE – High Energy Astrophysical Phenomena. Cosmic ray production, acceleration, propagation, detection. Gamma ray astronomy and bursts, X-rays, charged particles, supernovae and other explosive phenomena, stellar remnants and accretion systems, jets, microquasars, neutron stars, pulsars, black holes
5. astro-ph.IM – Instrumentation and Methods for Astrophysics. Detector and telescope design, experiment proposals. Laboratory Astrophysics. Methods for data analysis, statistical methods. Software, database design
6. astro-ph.SR. – Solar and Stellar Astrophysics. White dwarfs, brown dwarfs, cataclysmic variables. Star formation and protostellar systems, stellar astrobiology, binary and multiple systems of stars, stellar evolution and structure, coronas. Central stars of planetary nebulae. Helioseismology, solar neutrinos, production and detection of gravitational radiation from stellar systems.

We are looking for experienced scientists in any of these areas, and it would be useful to have people who can cover a range of subjects (as some of our existing editors do). As I mentioned here, our most popular area is 1 (Astrophysics of Galaxies) but 2 (Cosmology and NonGalactic Astrophysics) is running it a close second. While I would welcome offers from people with expertise in either of those fields, Editors in any of the other areas listed above would be welcome additions. Since we don’t charge authors or readers we can not offer payment to Editors but it is nevertheless a way of providing a service to the community.

If you’re interested, please get in touch either through the Open Journal website here, or through a message Mastodon here, BlueSky here, or LinkedIn here.

Peter Coles
Editor-in-Chief
Open Journal of Astrophysics

This is a version of a piece I posted yesterday on the OJAp blog.

Weekly Update from the Open Journal of Astrophysics 17/10/2026

It’s Saturday again, so it’s time for another update of activity at the Open Journal of Astrophysics. Since the last update we have published a further eight papers, bringing the number in Volume 9 (2026) to 245 and the total so far published by OJAp up to 693. There was no arXiv update on Monday 12th October owing to a US holiday, and I was on strike on Wednesday 14th October, so there were no papers published on either 13th or 14th October.

I continue to include the posts made on our Mastodon account (on Fediscience); these announcements also contain a clickable form of the DOI for each paper. Our Mastodon account has regular updates and other announcements from OJAp too, including posts from the OJAp blog.

The first new paper this week was published on Monday 12th October in the folder High-Energy Astrophysical Phenomena. The title is “Search for Gamma-ray emission from Abell 119 galaxy cluster using INTEGRAL/ISGRI, COMPTEL, and DAMPE data” by Siddhant Manna & Shantanu Desai (IIT Hyderabad Kandi, India. The study conducted a thorough search for non-thermal high-energy gamma-ray emission from the Abell 119 galaxy cluster using archival observations, but found no significant emission.

The overlay for this one is here:

You can find the officially accepted version on arXiv here and the announcement on Fediverse here:

https://fediscience.org/@OJ_Astro/117426708372504596

The second paper for this week, also published on Monday 12th October, is “Fast Astronomical Transients in Archival Photographic Plates: Using optical aberrations as a tool for discerning real images, from plate artifacts” by Ivo Busko (Independent Researcher). This study supports the idea that fast astronomical transients detected in 1950s Palomar sky surveys are not just plate artifacts, but potentially genuine off-axis point sources. It is in the folder Instrumentation and Methods for Astrophysics.

The overlay looks like this:

The official version of the paper can be found on arXiv here and the Fediverse announcement here:

https://fediscience.org/@OJ_Astro/117426761469024797

The third paper of the week, published on Thursday 15th October in the folder Instrumentation and Methods for Astrophysics, is “Differentiable Optics with dLux II: Optical Design Maximising Fisher Information” by Louis Desdoigts (Leiden Obs., NL), Benjamin Pope (Macquarie U., AU), Michael Gully-Santiago (U. Texas Austin, USA) & Peter Tuthill (U. Sydney, Australia).

The overlay for this is here:

The accepted version of this one can be found on the arXiv here and the Mastodon announcement here:

https://fediscience.org/@OJ_Astro/117443565520370980

The fourth new article of the week, also published on Thursday 15th October, in the folder Astrophysics of Galaxies is “The Lumina Project: Intergalactic Clumping and Recombination Sinks” by Ali Sadain (U. Texas Dallas, USA) and 12 others based in the USA, S. Korea and Germany. The study uses simulations to examine the uneven recombination rates during the Epoch of Reionization, finding a universal clumping evolution and discrepancies in recombination rates due to photoheating.

The overlay is here:

The official version of the paper can be found on arXiv here and the Fediverse announcement here:

https://fediscience.org/@OJ_Astro/117443648979460175

Paper Number Five for the week is “Blast.jl: Differentiable Non-Limber Power Spectra for Joint Clustering, Shear, and CMB lensing Analyses” by Sofia Chiarenza (U. Waterloo, Canada) and 6 others based in Canada, Italy, France and USA. This study, which is in the folder Cosmology and Nongalactic Astrophysics, presents an enhanced version of Blast.jl, a toolkit for computing non-Limber angular power spectra, incorporating various cosmological effects. Despite increased complexity, it maintains efficiency and supports gradient-based inference. It was also published on Thursday 15th October.

The overlay is here:

The officially-accepted version of the paper can be found on arXiv here and the Fediverse announcement here:

https://fediscience.org/@OJ_Astro/117443713467579735

Sixth one up is “EMU detection of mysterious multiple component radio-continuum emission from nearby spiral Seyfert I type galaxy ‘Sand-timer’ (NGC 7213)” by Miroslav Filipović (Western Sydney U., Australia) and an international cast of 26 others. The observations presented in this paper reveal peculiar emissions and previously undetected features in the ‘Sand-timer’ galaxy NGC 7213, possibly due to black hole activity or a tidal disruption event.

The overlay is here:

The officially-accepted version of this paper is on arXiv here and the Mastodon announcement on the fediverse here:

https://fediscience.org/@OJ_Astro/117443713467579735

The seventh paper of the week is “pynucastro 3: A community library for nuclear astrophysics” by Zhi Chen (Stony Brook U., USA) and 10 others, all based in the USA. This was published on Friday 16th October, i.e. yesterday, in the folder Instrumentation and Methods for Astrophysics. This article announces the latest release of pynucastro, a python library for nuclear astrophysics, includes new rate approximations, a stellar equation of state, StarLib support, and network exploration tools.

The overlay is here:

The officially accepted version is on arXiv here and the Mastodon announcement here:

https://fediscience.org/@OJ_Astro/117444752698463999

The eighth, and last, of the new papers for this week is “A Deep Look at the Ultra-Faint Milky Way Satellite Virgo III with Rubin Observatory Data Preview 2” by Aashay Pai (U. Chicago, USA) and 12 others based in the USA. This study uses data from the Vera C. Rubin Observatory to analyze the ultra-faint Milky Way satellite, Virgo III, confirming Virgo III’s properties as an ultra-faint dwarf galaxy.

The overlay is here:

The final version of this paper is on the arXiv here and the Mastodon announcement here:

https://fediscience.org/@OJ_Astro/117449310339264054

That concludes this week’s update. I anticipate that we’ll pass the 250 mark for 2026 next week, which means we’re well on target to publish over 300 papers and reach the 750 mark by the end of the year. I’ll do another update next weekend.

Weekly Update from the Open Journal of Astrophysics 10/10/2026

It’s Saturday again, so it’s time for another update of activity at the Open Journal of Astrophysics. Since the last update we have published a further eight papers, bringing the number in Volume 9 (2026) to 237 and the total so far published by OJAp up to 685.

I continue to include the posts made on our Mastodon account (on Fediscience); these announcements also contain a clickable form of the DOI for each paper. Our Mastodon account has regular updates and other announcements from OJAp too, including posts from the OJAp blog.

The first new paper this week was published on Monday 5th October in the folder Solar and Stellar Astrophysics. The title of the paper is “Diameters and Temperatures VII: High-angular resolution measurements of Solar-type stars with the CHARA Array” and it isby Tabetha Boyajian (Louisiana State University, USA) and 10 others based in the USA and Australia. This study uses interferometric measurements to determine precise characteristics of 27 nearby solar-type stars, including their radii, effective temperatures, and luminosities. The findings represent benchmarks for testing stellar evolutionary theory.

The overlay for this one is here:

You can find the officially accepted version on arXiv here and the announcement on Fediverse here:

https://fediscience.org/@OJ_Astro/117387213836435395

The second paper for this week, published on Tuesday 6th October, is “The jet-shaped pipe morphology in planetary nebulae and core-collapse supernova remnants” by Jessica Braudo and Noam Soker (Technion, Israel). This article, published in the folder High-Energy Astrophysical Phenomena, he study suggests that jets shape the ‘pipe’ structures in core-collapse supernova remnants and jet-shaped planetary nebulae, based on comparisons with hydrodynamical numerical simulations.

The overlay looks like this:

The official version of the paper can be found on arXiv here and the Fediverse announcement here:

https://fediscience.org/@OJ_Astro/117392678606207435

The third paper of the week, “Balancing bias, baryons, and scale cuts in LSST 3x2pt analysis” is by Ottavia Truttero (U. Edinburgh, UK) and 5 others on behalf of the The LSST Dark Energy Science Collaboration. It was published on Tuesday 6th October in the folder Cosmology and Nongalactic Astrophysics and presents a new analysis for LSST Y1 and Y10 data, exploring the effects of galaxy bias and baryonic feedback. The article also introduces a new open-source pipeline, MGL.

The overlay for this is here:

The accepted version of this one can be found on the arXiv here and the Mastodon announcement here:

https://fediscience.org/@OJ_Astro/117392776835315772

The fourth new paper of the week, published on Wednesday 7th Octonber, in the folder Solar and Stellar Astrophysics, is “High-Precision Differential Radial Velocities of C3PO Wide Binaries: A Test of Modified Newtonian Dynamics (MOND)” by Serat M. Saad and Yuan-Sen Ting (Ohio State University, USA). The paper describes a technique to measure differential radial velocities of wide-binary stars, improving precision and enabling better analysis of Modified Newtonian Dynamics (MOND), suggesting tension with current estimates of the acceleration scale.

The overlay is here:

The official version of the paper can be found on arXiv here and the Fediverse announcement here:

https://fediscience.org/@OJ_Astro/117398493738710737

Paper Number Five for the week is “Simulating the jittering-jets explosion mechanism: circum-jet rings account for observed core-collapse supernova remnant morphologies” by Muhammad Akashi & Noam Soker (Technion, Israel). The study uses 3D simulations to explore core-collapse supernova explosions driven by jets, supporting the jittering jets explosion mechanism theory. The simulations explain observed circum-jet rings in supernova remnants. This was also published on Wednesday 7th October, but in the folder High-Energy Astrophysical Phenomena.

The overlay is here:

The officially-accepted version of the paper can be found on arXiv here and the Fediverse announcement here:

https://fediscience.org/@OJ_Astro/117398573868529566

The sixth paper of the week is “Radio Continuum Study of One of the Brightest Large Magellanic Cloud Supernova Remnant N 132D” by Rami Z. E. Alsaberi (Western Sydney U. Australia) and 7 others. This was the first of three papers published on Friday 9th October, and it is in the folder High-Energy Astrophysical Phenomena. This one presents a radio continuum analysis of the Large Magellanic Cloud supernova remnant N 132D, revealing insights into its magnetic field structure, energetic properties, and particle acceleration.

The officially-accepted version of this paper is on arXiv here and the Mastodon announcement on the fediverse here:

https://fediscience.org/@OJ_Astro/117409740216472768

The seventh paper of the week is “New Signs Pointing Toward a Correlation Between Astrophysical Neutrinos and Radio Flares” by Yjan Gordon (U. Wisconsin-Madison), Peter S. Ferguson (U. Washington), Eric J. Hooper & Michael N. Martinez (U. Wisconsin-Madison); all in the USA. This was also published on Friday 7th October, but in the folder Astrophysics of Galaxies. It is very topical, in the light of the award of this year’s Nobel Prize for Physics to Francis Halzen for his work on IceCube. The paper explains how data from VLASS and IceCube Neutrino Observatory reveal a correlation between radio variability and astrophysical neutrino detection, suggesting radio flares contribute to about 13% of astrophysical neutrinos detected by IceCube.

The overlay is here:

The officially accepted version is on arXiv here and the Mastodon announcement here:

https://fediscience.org/@OJ_Astro/117409801852226309

The eighth, and last, of the new papers for this week is “Spectroscopic follow-up of compact object binary candidates from Gaia DR3: White dwarfs, neutron stars, black holes, and the parallax zeropoint” by Kareem El-Badry (Caltech, USA) and an international cast of 14 others. This paper uses data from Gaia DR3 to analyze orbits of binary systems, including potential black holes, neutron stars, and white dwarfs. It was published on Friday 9th October, i.e. yesterday, in the folder Solar and Stellar Astrophysics.

The overlay is here:

The final version of this paper is on the arXiv here and the Mastodon announcement here:

https://fediscience.org/@OJ_Astro/117409906391375973

That concludes this week’s update. We’re still on target to publish over 300 papers and reach the 750 mark by the end of the year. I’ll do another update next week.

Weekly Update from the Open Journal of Astrophysics 03/10/2026

It’s Saturday again, so it’s time for another update of activity at the Open Journal of Astrophysics. Since the last update we have published a further 13 papers, including one correction to an article already published, bringing the number in Volume 9 (2026) to 229 and the total so far published by OJAp up to 677. This would have been a busy week even without the clutch of four MEGATRON papers announced on Wednesday!

I continue to include the posts made on our Mastodon account (on Fediscience); these announcements also contain a clickable form of the DOI for each paper. Our Mastodon account has regular updates and other announcements from OJAp too, including posts from the OJAp blog.

The first new paper this week was published on Tuesday 28th September in the folder Solar and Stellar Astrophysics. The title is “Phlegethon: a fully compressible magnetohydrodynamic code for simulations in stellar astrophysics” and it is by G. Leidi (Heidelberger Institut für Theoretische Studie, Germany) and 14 others. PHLEGETHON is a magnetohydrodynamic code designed for multidimensional simulations in stellar astrophysics, capable of modeling a wide range of dynamical processes in stars. It is publicly accessible online.

The overlay for this one is here:

You can find the officially accepted version on arXiv here and the announcement on Fediverse here:

https://fediscience.org/@OJ_Astro/117353123029298309

The second paper for this week, published on Tuesday 29th September, is “The impact of source and survey modelling on the connection between [O III] emitters and Ly-α forest transmission at z ~ 6” by Luke Conaboy (U. Nottingham, UK) and 5 others based in the UK, India and Germany. This study improves theoretical work on the connection between galaxies and the intergalactic medium, using an empirical model and James Webb Space Telescope surveys. It is in the folder marked Cosmology and Nongalactic Astrophysics.

The overlay looks like this:

The official version of the paper can be found on arXiv here and the Fediverse announcement here:

https://fediscience.org/@OJ_Astro/117353186706460890

Next we have four related papers produced by the MEGATRON Project, led by Harley Katz (U. Chicago) and Martin Rey (U. Bath, UK), Corentin Cadiou (IAP Paris, France). These were all published on Wednesday 30th September in the folder Astrophysics of Galaxies.

I mentioned this in a separate blog post here, so I won’t describe them in detail again here. Here are the four overlays:

The Mastodon announcement for these is in the form of a thread:

https://fediscience.org/@OJ_Astro/117360208450162112

The four papers can be found on arXiv here, here, here and here.

The four MEGATRON papers were not the only ones published on Wednesday 30th September, however. We published “The Chirp-Mass Ladder: A New Rung Emerges” by Vaibhav Tiwari (U. Birmingham, UK) in the folder High-Energy Astrophysical Phenomena on that day too. This paper presents an analysis of 256 binary black-hole (BBH) events, suggesting a hierarchical merger scenario to explain the structured mass distribution, and encouraging further investigation into hierarchical mergers’ role in the BBH population. The overlay for this is here:

The accepted version of this one can be found on the arXiv here and the Mastodon announcement here:

https://fediscience.org/@OJ_Astro/117360976282043649

The eighth new paper of the week, published on Thursday 1st October 2026, in the folder Cosmology and Nongalactic Astrophysics, is “A Consistent Implementation of Cluster Strong Lensing in Cosmological Simulation Light Cones” by Cian Roche (MIT, USA) and 11 others based in the USA, Germany and Italy.

The overlay is here:

The official version of the paper can be found on arXiv here and the Fediverse announcement here:

https://fediscience.org/@OJ_Astro/117313452009130829

We now have four papers all published on Friday 2nd October (i.e. yesterday).

The first of this batch is “Analytical weak-lensing shear response of galaxy model fitting” by Xiangchong Li (Brookhaven National Laboratory, USA). This is in the folder marked Cosmology and Nongalactic Astrophysics: it explores how galaxy model fitting responds to weak-lensing shear distortions using a new algebraic system, quintuple numbers, within the AnaCal framework, keeping multiplicative bias low.

The overlay is here:

The officially-accepted version of the paper can be found on arXiv here and the Fediverse announcement here:

https://fediscience.org/@OJ_Astro/117369829010377996

The 10th paper of the week is “Evidence for inefficient dust production in a massive, metal-rich galaxy at z=7.13 uncovered by JWST and ALMA” by Kasper E. Heintz (Cosmic Dawn Center, Copenhagen, Denmark) and 19 others in Europe, UK and USA. This article, published on Friday 2nd October 2026, in the folder Astrophysics of Galaxies, analyzes cosmic dust in high redshift galaxies, specifically A1689-zD1, using data from JWST and ALMA, suggesting dust formation and destruction processes differ for galaxies in the early Universe.

The officially-accepted version of this paper is on arXiv here and the Mastodon announcement on the fediverse here:

https://fediscience.org/@OJ_Astro/117369922539182969

The 11th paper of the week is “Starbursts hiding in the main sequence: a pathway toward quenching?” by Florent Renaud (Observatoire Astronomique de Strasbourg, France) and 12 others based in France and UK. This article explores the “starbursts in the main sequence” (SBMSs) that intermittently appear in galaxy evolution, attributing their existence to earlier stellar mass assembly and frequent mergers. It was published on Friday 2nd October 2026, in the folder Astrophysics of Galaxies.

The overlay is here:

The officially accepted version is on arXiv here and the Mastodon announcement here:

https://fediscience.org/@OJ_Astro/117369978824690794

The twelfth, and last, of the new papers for this week is “Ring Position Angles and Spin in M87* and Sgr A*” by Nicholas S. Conroy (U. Illinois at Urbana-Champaign, USA) and 6 others all based in the USA. This was also published on Friday 2nd October but in the folder High-Energy Astrophysical Phenomena.

The overlay is here:

The final version of this paper is on the arXiv here and the Mastodon announcement here:

https://fediscience.org/@OJ_Astro/117370029522771607

And finally, on Monday 28th September we announced one (minor) correction to a previously published article. The overlay of the correction notice is here:

The mastodon announcement is here:

https://fediscience.org/@OJ_Astro/117347566188359426

The corrected version of this paper can be found on arXiv here.

That concludes this week’s update. As things are going we seem likely to publish over 300 papers this year, and may reach the 750 mark by the end of the year too. I’ll do another update next week.

The arXiv limit

Putting my community service hat on, I thought I would relay an announcement on the an announcement on the arXiv blog that it is introducing a limit on the rate that any individual can submit papers to arXiv. To start with, the limit will be two per month. This limit applies to the submitter, not to all the authors, so I think large collaborations will find a way around it by having different co-authors do the submissions.

The reason for this limit is very clear:

The rate of submissions is currently growing in an uncontrolled and alarming way. Most of this growth is driven by AI, which makes it very easy for authors to flood the arXiv with boilerplate papers. All this is making life impossible for the moderators. It will be very interesting to see if this move manages to stem the tide.

If you have any questions, please read the FAQ on the page here. One thing I’m not sure about is whether the limit applies to replacements as well as new submissions. It doesn’t seem to be addressed in the FAQs.

A MEGATRON Day!

Today we published four papers at the Open Journal of Astrophysics all related to the Megatron Project which is co-led by Martin Rey of the University of Bath (UK), Harley Katz of the University of Chicago (USA) and Corentin Cadiou of the Institut d’Astrophysique de Paris in France. I will include this quartet in my regular weekly update on Saturday but there is a press release accompanying these publications so I thought I’d splash them a bit here too.

I’ll show the overlays on Saturday but in the meantime here are some pretty graphics from three of the papers:

In no particular order the four papers are:

MEGATRON: Reproducing the Diversity of High-Redshift Galaxy Spectra with Cosmological Radiation Hydrodynamics Simulations

MEGATRON: how the first stars can create an iron metallicity plateau in the smallest dwarf galaxies

MEGATRON: the impact of non-equilibrium effects and local radiation fields on the circumgalactic medium at cosmic noon”

MEGATRON: The Physical Origins of Steep UV Slopes at high redshift

The Press Release from the University of Bath is reproduced below. A Press Release in French can be found here.

–o–

New simulations connect the first stars to cosmic fingerprints still visible today

International MEGATRON project links space telescope observations of the infant Universe with the chemical fossil record of the Milky Way.

Researchers have used some of the most detailed simulations yet of the early Universe to investigate how the first stars and galaxies formed.

Led by researchers at the University of Bath, alongside collaborators at the University of Chicago in the US and the Institut d’Astrophysique de Paris in France, the MEGATRON project uses advanced simulations to explore how the first stars and galaxies lit up the previously dark cosmos and enriched it with the chemical elements that would later become the building blocks of everything around us.

Published today in the Open Journal of Astrophysics, four studies from the MEGATRON project combine cutting-edge cosmological simulations with sophisticated models of radiation, chemistry and galaxy formation. Together, these constitute the collaboration’s first substantial body of published results, with further papers expected to follow.

The findings from the study of the first stars show that accurately capturing the interplay between starlight, gas and newly forged elements is essential for connecting two previously separate views of the early Universe: observations of young galaxies by the James Webb Space Telescope (JWST) and the chemical clues preserved in ancient stars in and around the Milky Way – the galaxy that contains our Solar System.

JWST provides a direct view of galaxies in the infant Universe, while ancient stars act as a fossil record of cosmic history. By studying the chemical fingerprints of these ancient stars, astronomers can reconstruct the properties of the first stars and trace how they enriched the cosmos with the first chemical elements.

The simulations follow the evolution of a young galaxy that will eventually grow into a system similar in mass to the Milky Way. Using advanced computer models that simultaneously track the movement of gas, the propagation of starlight and the evolution of chemical concentrations, the team investigated how stars shape the gas in and around galaxies over billions of years.

The study suggests that simplified models may underestimate the influence of stellar radiation and complex chemical processes on the gas surrounding galaxies. By modelling these effects at exceptionally high resolution, the team resolved structures in the gas that are not captured by simpler models, helping to improve predictions for current and future astronomical observations.

A direct glimpse of the infant cosmos

Dr Martin Rey from the Department of Physics at the University of Bath and a lead contributor to the MEGATRON collaboration, said: “The James Webb Space Telescope gives us a direct glimpse of the infant cosmos, while stellar archaeology allows us to study the relics of those earliest times in our own Galactic neighbourhood. MEGATRON provides a physical bridge between the two.”

The simulations begin with pristine gas containing no heavy elements, mirroring conditions shortly after the Big Bang. They then follow the birth of the first stars, the radiation they emit, the supernova explosions that mark their deaths and the dispersal of newly forged elements into subsequent generations of stars and galaxies.

Understanding this process is central to one of astronomy’s most fundamental questions: where the elements that make up today’s Universe came from.

Dr Rey said: “The elements that make our world and life possible – carbon, oxygen, iron and many others – were forged by stars. To understand where those elements came from, we need to understand how the first stars formed and enriched their surroundings. MEGATRON allows us to test these ideas directly by comparing detailed simulations with observations from JWST and the chemical fingerprints preserved in ancient stars.”

Looking ahead, the team plans to use MEGATRON to strengthen links between theory and emerging observational data. As JWST continues to transform our understanding of the earliest galaxies, large-scale stellar surveys will provide increasingly detailed information about ancient stars in and around the Milky Way.

Dr Rey and his colleagues at Bath are already developing the next generation of simulations. The project has been awarded 40 million processor hours on the UK’s national supercomputers, equivalent to running five million laptops in parallel for a year. These resources will enable simulations with higher resolution and more complete physical models, allowing even more direct comparisons with JWST observations and the chemical fossil record preserved in ancient stars.

“MEGATRON provides a common physical framework for interpreting two of astronomy’s most exciting new datasets: JWST’s view of the earliest galaxies and the stellar fossil record,” said Dr Rey. “Together, these complementary observations allow us to test competing models of the first stars in ways that weren’t previously possible.”

The MEGATRON project started in 2023 and is scheduled to run until 2030.

The Open Journal of Astrophysics is a Q1 Journal

I was a meeting this morning about other things during the course of which I found out that, as of 2025, the Open Journal of Astrophysics is a Q1 journal. This means that according to certain bibliometric criteria, OJAp is in the first quartile (i.e. top 25%) of journals in its field. You can find a table with all journals in Astronomy and Astrophysics curated by SCImago here. I searched the list for all the journals that are classified as Diamond Open Access and found that we’re the only one:

As with many of these bibliometric things the data are incorrect. We actually published 212 papers in 2025. The number of citations is wildly wrong too – the true figure is much higher. I presume that the number of documents (3 years) is 2022+2023+2024, which is the correct number if that’s what it is meant to represent.

My main objection to journal indicators like this (apart from the fact that they’re usually riddled with errors) is that nowadays it is quite easy to extract citation information at the article level so there’s no reason to use a metric associated with the journal to judge the quality of a paper. It’s like judging a book by its cover. I hate Journal Impact Factor for similar reasons; see posts here.

For this reason I don’t personally care at all about whether OJAp is Q1 or Q2 or whatever. I do recognize, however, that many astronomers and astrophysicists work in countries where the funding agencies do not count papers unless they are in Q1 journals. I think that’s silly, but it’s a fact of life.

If the only reason you were not submitting papers to OJAp was that it wasn’t a Q1 journal then you can start submitting them now!

A “Full House” at the Open Journal of Astrophysics!

In my recent weekly updates of activity at the Open Journal of Astrophysics, the latest of which is here, I’ve remarked that we had built up quite a backlog of papers accepted but yet to be published. This is no doubt due to August being a holiday for many researchers. Well, we seem to be catching up rather rapidly. So far this week we have published eight new papers, and it’s only Wednesday!

The recent burst of activity has led to us establishing a first, a week in which we have published a full house of at least one paper in each of the six sections of astro-ph on the arXiv. As a reminder, these are they:

1. astro-ph.GA – Astrophysics of Galaxies. Phenomena pertaining to galaxies or the Milky Way. Star clusters, HII regions and planetary nebulae, the interstellar medium, atomic and molecular clouds, dust. Stellar populations. Galactic structure, formation, dynamics. Galactic nuclei, bulges, disks, halo. Active Galactic Nuclei, supermassive black holes, quasars. Gravitational lens systems. The Milky Way and its contents
2. astro-ph.CO – Cosmology and Nongalactic Astrophysics. Phenomenology of early universe, cosmic microwave background, cosmological parameters, primordial element abundances, extragalactic distance scale, large-scale structure of the universe. Groups, superclusters, voids, intergalactic medium. Particle astrophysics: dark energy, dark matter, baryogenesis, leptogenesis, inflationary models, reheating, monopoles, WIMPs, cosmic strings, primordial black holes, cosmological gravitational radiation
3. astro-ph.EP – Earth and Planetary Astrophysics. Interplanetary medium, planetary physics, planetary astrobiology, extrasolar planets, comets, asteroids, meteorites. Structure and formation of the solar system
4. astro-ph.HE – High Energy Astrophysical Phenomena. Cosmic ray production, acceleration, propagation, detection. Gamma ray astronomy and bursts, X-rays, charged particles, supernovae and other explosive phenomena, stellar remnants and accretion systems, jets, microquasars, neutron stars, pulsars, black holes
5. astro-ph.IM – Instrumentation and Methods for Astrophysics. Detector and telescope design, experiment proposals. Laboratory Astrophysics. Methods for data analysis, statistical methods. Software, database design
6. astro-ph.SR – Solar and Stellar Astrophysics. White dwarfs, brown dwarfs, cataclysmic variables. Star formation and protostellar systems, stellar astrobiology, binary and multiple systems of stars, stellar evolution and structure, coronas. Central stars of planetary nebulae. Helioseismology, solar neutrinos, production and detection of gravitational radiation from stellar systems.

As of yesterday we had published in five of the six categories and were only missing a paper (in Number 4 – High-Energy Astrophysical Phenomena). Today, right on cue, from the queue, came this paper to complete the set:

There’s still a couple of days to go and we have more papers in the pipeline so it looks like I’ll have a busy time on Saturday morning when I do the next update!

Our Two-Million-Dollar Journal!

It’s exactly a year since I pointed out that the Open Journal of Astrophysics had saved the astrophysics research community worldwide a sum in excess of a million dollars in publication costs.

The Article Processing Charge (APC) for publishing a paper in Monthly Notices of the Royal Astronomical Society (MNRAS) is now £2356. Converting that to dollars at current rates (£1=$1.36) gives about $3200 per paper.

As of today, 25th August 2026, the Open Journal of Astrophysics has published 632 articles. Using the dollar cost of an MNRAS APC as a benchmark – many journals charge more – this means that we have now saved the global astrophysics community over $2M (for a total outlay of around $15K).

Yes, we are still a small journal but the size of that figure should help you understand how much money is being wasted globally on publishing fees that could instead be spent on actual research.

It’s good to see that more and more researchers are seeing the light and switching to Diamond Open Access. Today we published the 184th article in Volume 9 (2026) of the Open Journal of Astrophysics. At the end of August we will be about two-thirds of the way through the year so I expect we will publish more than 270 articles this year. I also expect that less than a year from now we will have saved our third million dollars.

I’d like to take this opportunity to thank everyone involved in running this journal: the Editors, staff at Maynooth University Library who help us, the host of volunteer referees, and of course our authors. I’m confident that, together, we can change the publishing landscape in astrophysics, and put the power (and money) back in the hands of researchers instead of greedy publishers.

This is a slightly-edited version of a post I made yesterday, when we had published four fewer papers, for the Open Journal of Astrophysics blog.

News from arXiv…

I saw recently an announcement that arXiv – which recently became a standalone nonprofit organization – now hosts more than three million articles. That message took me to a post on the arXiv blog from which I learnt that said blog is on WordPress which makes it possible to include embedded links from this WordPress blog, i.e.:

https://blog.arxiv.org/2026/07/09/arxiv-now-hosts-over-3-million-articles/?page_id=1854

This in turn reminded me to answer a question that people sometimes ask about the Open Journal of Astrophysics, namely what would happen if arXiv went offline? Since OJAp is an arXiv-overlay journal this would appear to be fatal. We have been keeping duplicates of all the papers we publish, and associated metadata, in a local repository so that if arXiv went down we could reistate them fairly quickly. All we would need to do is alter the overlay to point to a different web address: there is no reason at all why the overlay idea can’t be adapted to other forms of repository.

Recently, however, arXiv decided to do a similar thing for all its articles. Here is a blog post about it:

https://blog.arxiv.org/2026/02/03/arxiv-future-proofs-access-to-research-with-third-party-digital-preservation/

I blogged about the first stage of this here.

Anyway, if you use arXiv at all – which will include most astrophysicists – then it would be a good idea to follow the arXiv blog as there is very important news on it, including information about alterations to the schedule of announcements.

A Ban on Publication Fees?

Yesterday I was going through the “onboarding” process via Zoom with two new Editors at the Open Journal of Astrophysics (OJAp) when one of them mentioned a recent policy decision at the USA which means we’ll probably get even more papers submitted from there. I wasn’t aware of the decision, but there’s an article in the Times Higher about it here.

In a nutshell:

Under proposed rule changes published by the Office of Management and Budget, all journal publication costs – “including page charges, article processing charges (APCs), or similar fees such as open access fees for professional journal publications and other peer-reviewed publications” – will become “unallowable under federal awards”.

It is important to stress that at this stage the change is proposed rather than actual and it remains to be seen whether it will stand. I think it should because publication fees, article processing charges or whatever you call them are a complete waste of money.

The Times Higher article frames this as “Trump’s ban on paying open access fees”. I was worried to be finding myself in agreement with Donald Trump on anything, but I very much doubt that Trump himself knows anything about scientific publishing or has had much of a hand in this decision. It seems to me to be eminently sensible to ensure that funds meant to be directed at research are not frittered away on page charges. If I were involved in running a research institution I would make it a disciplinary offence to spend money on publication fees.

Of course the academic publishing industry is upset about the proposal claiming that scientific publishing is “high cost”, which it is but only because the publishers rake in huge profits. The way forward, as I have argued many times (e.g. here), is Diamond Open Access, a exemplified by OJAp. The marginal cost per paper article published for OJAp is just $10 and we have at least as much impact as the other leading journals in astrophysics.

I have been surprised how many researchers from the USA are already using OJAp, including many from top institutions such as Harvard, Caltech, Princeton and Chicago. The surprise is basically that authors from the USA have for many years been used to paying page charges for publishing in the Astrophysical Journal and others from the AAS stable. This was the case even before digital journals came on the scene and well before the Open Access movement. I suppose American authors put up with page charges because they felt they had to, but that is no longer the case.

Will we get even more submissions from the USA as a result of this policy change? We’ll just have to wait and see…

P.S. This morning I published the 600th paper at the Open Journal of Astrophysics.

On the Use of Generative AI

We’ve reached the time of year at Maynooth when academic staff are busy grading projects of various kinds. This year we have to be much mindful of the use of Large Language Models (such as ChatGPT) in written reports as these are much more commonplace now. We anticipated this at the start of the academic year, but now we have to see whether are policies work in practice. In the case of the Computational Physics projects that I have to mark, this also extends to the use of Generative AI in writing code. The approach I take there is that I don’t place an absolute ban, but I require students to declare the use and, crucially, describe what steps they used to test and validate the output. By the time they’ve done that they might as well have written the code themselves!

As well as its effect on teaching, GenAI is having a huge impact on research. In my role as Managing Editor of the Open Journal of Astrophysics I have seen a large increase in submissions of papers in which AI plays some role. These vary from pure “slop” – nonsense papers not worthy of serious consideration – to articles that use AI tools in a perfectly reasonable way to speed up certain aspects of the analysis. I think this is the case for most scientific journals.

The approach we have adopted is similar to the policy on teaching outlined above. It is described by the following section we have added to our “For Authors” page:

Use of Generative AI. We do not operate a blanket ban on the use of Large Language Models (LLMs) or other forms of Generative AI. If you do use such tools, however, you must declare it in the acknowledgments section of your paper. Furthermore, if GenAI methods are used for any form of calculation, analysis, or data visualization you must include an account of what steps you have taken to test and validate these methods. Articles containing direct evidence of the use of GenAI, such as hallucinated references or prompts embedded in the text, will not be accepted.

Since the Open Journal of Astrophysics is an arXiv-overlay journal I should also pass on the information that arXiv is itself developing a policy on the use of LLMs. Although it has yet to appear on the arXiv website, a recent communication on social media states:

If there is incontrovertible evidence of LLM slop in a paper, this means the authors did not take the time to read the LLM output and we can’t trust anything else in the paper. Penalty is 1 year ban from arXiv followed by a requirement that subsequent arXiv submissions must first be accepted at a reputable peer-reviewed venue.

This will be tantamount to a one-year ban from publishing in OJAp, so urge authors should be be very careful in their use of such methods.

It is likely that these policies will have to be extended as the use of GenAI spreads.

Editorial Opportunity at the Journal of Open Source Software

The Journal of Open Source Software – known to its friends as JOSS – is is a developer friendly, diamond open access journal for research software packages which has been running since 2016 and is enormously successful, publishing Open Source software across many fields of science. Its UR, joss.theoj.org, is a giveaway that it is a stablemate of astro.theoj.org, aka the Open Journal of Astrophysics.

The driving force behind JOSS, responsible for getting it off the ground at the very beginning, is Arfon Smith whom I’ve known since Nottingham days and it iis fair to say that without his considerable help, OJAp would never have started. Both journals started off as speculative ventures, and OJAp has taken a considerable time to establish itself, but JOSS took off very quickly indeed and has now published over 3,500 papers. There are numerous differences between the two journals but, like OJAp, all publications in JOSS are free to authors and readers.

Arfon has held the role of Editor-in-Chief at JOSS since 2016 but in a recent blog post he explains that he is stepping down from his role as Editor-in-Chief, although he will remain at JOSS. The call for a replacement is here. It’s an opportunity that will appeal to anyone interested in open-source research software and open-access publishing so if that’s you then please consider applying. It will be a substantial investment of time, probably about a day a week. I quote:

Candidates should have the capacity to commit the time this role requires. For those in institutional positions, we ask for a brief letter or statement from your employer or supervisor confirming support for this commitment. Independent researchers, consultants, or others without a traditional institutional affiliation should include a brief statement describing how they plan to allocate the time.

P.S. Today OJAp published its 100th paper of 2026 so far…

P.P.S. I’ll be stepping down as Editor-in-Chief at OJAp in a couple of years, when I retire, and we’ll be doing a similar search nearer the date.

Weekly Update from the Open Journal of Astrophysics – 07/02/2026

It’s Saturday once more so time for another update of activity at the Open Journal of Astrophysics. Since the last update we have published a further six papers, bringing the number in Volume 9 (2026) to 24 and the total so far published by OJAp up to 472.

I will continue to include the posts made on our Mastodon account (on Fediscience) to encourage you to visit it. Mastodon is a really excellent service, and a more than adequate replacement for X/Twitter which nobody should be using; these announcement also show the DOI for each paper.

The first paper to report this week is “The Impact of Star Formation and Feedback Recipes on the Stellar Mass and Interstellar Medium of High-Redshift Galaxies” by Harley Katz (U. Chicago, USA), Martin P. Rey (U. Oxford, UK), Corentin Cadiou (Lund U., Sweden) Taysun Kimm (Yonsei U., Korea) and Oscar Agertz (Lund). This paper was published on Monday 2nd February 2026 in the folder Astrophysics of Galaxies. It introduces MEGATRON, a new model for galaxy formation simulations, highlighting that feedback energy controls star formation at high redshift and highlighting the importance of the interstellar medium.

The overlay is here:

You can find the officially accepted version on arXiv here and the announcement on Fediverse here:

https://fediscience.org/@OJ_Astro/116000695648050758

The second paper is “Photometric Redshifts in JWST Deep Fields: A Pixel-Based Alternative with DeepDISC” by Grant Merz (U. Illinois at Urbana-Champaign) and 6 others, all based in the USA. This paper was published on Monday February 2nd 2026 in the folder Instrumentation and Methods for Astrophysics. This paper explores the effectiveness of the DeepDISC machine learning algorithm in estimating photometric redshifts from near-infrared data, demonstrating its potential for larger image volumes and spectroscopic samples

The overlay for this one is here:

The official version of the paper can be found on arXiv here and the Fediverse announcement here:

https://fediscience.org/@OJ_Astro/116000777572439111

Next, published on Wednesday 4th February in the folder Astrophysics of Galaxies, is “Inferring Interstellar Medium Density, Temperature, and Metallicity from Turbulent H II Regions” by Larrance Xing (U. Chicago, USA), Nicholas Choustikov (U. Oxford, UK), Harley Katz (U. Chicago) and Alex J. Cameron (DAWN, Denmark). This paper argues that supersonic turbulenc affects the interpretation of H II region properties, potentially impacting inferred metallicity, ionization, and excitation from in nebular emission lines, motivating more extensive modelling.

The overlay is here:

The official version can be found on arXiv here and the Fediverse announcement is here:

https://fediscience.org/@OJ_Astro/116011384659092223

The fourth paper this week, also published on Wednesday 4th February, but in the folder Solar and Stellar Astrophysics, is “A Systematic Search for Big Dippers in ASAS-SN” by B. JoHantgen, D. M. Rowan, R. Forés-Toribio, C. S. Kochanek, & K. Z. Stanek (Ohio State University, USA), B. J. Shappee (U. Hawaii, USA), Subo Dong (Peking University), J. L. Prieto Universidad Diego Portales, Chile) and Todd A. Thompson (Ohio State). This study identifies 4 new dipper stars and 15 long-period eclipsing binary candidates using ASAS-SN light curves and multi-wavelength data, categorizing them based on their characteristics.

Here is the overlay:

The official version can be found on arXiv here and the Fediverse announcement is here:

https://fediscience.org/@OJ_Astro/116011460612040834

Fifth, and next to last this week we have “Unveiling the drivers of the Baryon Cycles with Interpretable Multi-step Machine Learning and Simulations” by Mst Shamima Khanom, Benjamin W. Keller and Javier Ignacio Saavedra Moreno (U. Memphis, USA). This paper was published on Thursday 5th February 2026 in the folder Astrophysics of Galaxies. This study uses machine learning methods to understand how galaxies lose or retain baryons, highlighting the relationship between baryon fraction and various galactic measurements.

The overlay is here:

The accepted version can be found on arXiv here, and the fediverse announcement is here:

https://fediscience.org/@OJ_Astro/116016883984380622

Finally for this week we have “The Bispectrum of Intrinsic Alignments: II. Precision Comparison Against Dark Matter Simulations” by Thomas Bakx (Utrecht U., Netherlands), Toshiki Kurita (MPA Garching, Germany), Alexander Eggemeier (U. Bonn, Germany), Nora Elisa Chisari (Utrecht) and Zvonimir Vlah (Ruđer Bošković Institute, Croatia). This paper was accepted in December, but publication got delayed by the Christmas effect so was published on February 6th 2026, in the folder Cosmology and Nongalactic Astrophysics. This study uses N-body simulations to accurately measure three-dimensional bispectra of halo intrinsic alignments and dark matter overdensities, providing a method to determine higher order shape bias parameters.

The overlay is here:

You can find the published version of the article here, and the Mastodon announcement is here:

https://fediscience.org/@OJ_Astro/116022562915557971

And that concludes this week’s update. I will do another next Saturday.

Weekly Update from the Open Journal of Astrophysics – 31/01/2026

It’s Saturday once more so time for another update of activity at the Open Journal of Astrophysics. Since the last update we have published a further three papers, bringing the number in Volume 9 (2026) to 18 and the total so far published by OJAp up to 466.

I will continue to include the posts made on our Mastodon account (on Fediscience) to encourage you to visit it. Mastodon is a really excellent service, and a more than adequate replacement for X/Twitter which nobody should be using; these announcement also show the DOI for each paper.

The first paper to report this week is “Probing Stellar Kinematics with the Time-Asymmetric Hanbury Brown and Twiss Effect” by Lucijana Stanic (University of Zurich, Switzerland) and 13 others based in Zurich, Lausanne and Geneva (all in Switzerland). This was published on Monday 26th January 2026 in the folder Instrumentation and Methods for Astrophysics. This research demonstrates that intensity interferometry can reveal internal stellar kinematics, providing a new way to observe stellar dynamics with high time resolution.

The overlay is here:

You can find the officially accepted version on arXiv here and the announcement on Fediverse here:

https://fediscience.org/@OJ_Astro/115961234375736584

The second paper is “DIPLODOCUS I: Framework for the evaluation of relativistic transport equations with continuous forcing and discrete particle interactions” by Christopher N Everett & Garret Cotter (University of Oxford, UK). This was published on Tuesday January 27th 2026 in the folder High-Energy Astrophysical Phenomena. DIPLODOCUS is a new framework for mesoscopic modelling of astrophysical systems, using an integral formulation of relativistic transport equations and a discretisation procedure for particle distributions.

The overlay for this one is here:

The official version of the paper can be found on arXiv here and the Fediverse announcement here:

https://fediscience.org/@OJ_Astro/115966199181415094

Next, also published on Tuesday January 27th but in the folder Cosmology and Nongalactic Astrophysics we have “The Atacama Cosmology Telescope: DR6 Sunyaev-Zel’dovich Selected Galaxy Clusters Catalog” by M. Aguena et al. (101 authors altogether), on behalf of the ACT-DES-HSC Collaboration. This article reports on the discovery of 10,040 galaxy clusters in the Atacama Cosmology Telescope data, including 1,180 clusters at high redshifts, using the Sunyaev-Zel’dovich effect.

The overlay is here:

The official version can be found on arXiv here and the Fediverse announcement is here:

https://fediscience.org/@OJ_Astro/115966458299870033

And finally for this week we have a paper published yesterday, Friday 30th January 2026, in the folder Astrophysics of Galaxies. This is the paper I blogged about yesterday: “A Cosmic Miracle: A Remarkably Luminous Galaxy at zspec = 14.44 Confirmed with JWST” by Rohan Naidu (MIT Kavli Institute) and an international cast of 45 others. This article reports on the discovery by the James Webb Space Telescope (JWST) of a bright galaxy, MoM-z14, located 280 million years post-Big Bang, that challenges models of galaxy formation and the star-formation history of early galaxies.

The overlay is here:

The accepted version can be found on arXiv here, and the fediverse announcement is here:

https://fediscience.org/@OJ_Astro/115982837486159819

And that concludes the update for this week. I will do another next Saturday.

#ACTDESHSCCollaboration #arXiv250511263v2 #arXiv250721459v3 #arXiv250813296v4 #arXiv250913152v2 #AstridSimulations #AstrophysicsOfGalaxies #CosmologyAndNonGalacticAstrophysics #DiamondOpenAccess #DiamondOpenAccessPublishing #DIPLODOCUS #galaxyClusters #galaxyFormation #HanburyBrownAndTwiss #HighEnergyAstrophysicalPhenomena #InstrumentationAndMethodsForAstrophysics #JWST #largeScaleStructureOfTheUniverse #MoMZ14 #OpenAccess #OpenAccessPublishing #OpenJournalOfAstrophysics #PlasmaPhysics #relativisticTransportEquations #starFormation #StellarKinematics #SunyaevZeDovichEffect #TheOpenJournalOfAstrophysics

Weekly Update from the Open Journal of Astrophysics – 24/01/2026

It’s Saturday once more so time for another update of activity at the Open Journal of Astrophysics. Since the last update we have published a further three papers, bringing the number in Volume 9 (2026) to 14 and the total so far published by OJAp up to 462. This week was slightly affected by a Federal holiday in the USA on January 19th; there were no arXiv announcements the following day.

I will continue to include the posts made on our Mastodon account (on Fediscience) to encourage you to visit it. Mastodon is a really excellent service, and a more than adequate replacement for X/Twitter which nobody should be using.

The first paper to report this week is “The Properties of Little Red Dot Galaxies in the ASTRID Simulation” by Patrick LaChance, Rupert A. C. Croft, Tiziana Di Matteo & Yihao Zhou (Carnegie Mellon U.), Fabio Pacucci (Harvard-Smithsonian CfA), Yueying Ni (U. Michigan Ann Arbor), Nianyi Chen (Princeton U.) and Simeon Bird (UC Riverside), all based in the USA. This paper was published on Monday 19th January 2026 in the folder Cosmology and Nongalactic Astrophysics; the study analyses mock observations of “Little Red Dot” galaxies created from the ASTRID simulation, having high stellar masses and containing massive black holes; not all features match real observations.

The overlay is here:

You can find the officially accepted version on arXiv here and the announcement on Fediverse here:

https://fediscience.org/@OJ_Astro/115921308789068125

The second paper is “Angular bispectrum of matter number counts in cosmic structures” by Thomas Montandon (U. Montpellier, France), Enea Di Dio (U. Genève, Switzerland), Cornelius Rampf (Ruđer Bošković Institute, Croatia) and Julian Adamek (U. Zürich, Switzerland). This was published on Wednesday January 21st, also in the folder Cosmology and Nongalactic Astrophysics. This paper presents thee first full-sky computation of the angular bispectrum in second-order perturbation theory, offering insights into the Universe’s initial conditions, gravity, and cosmological parameters. The results align well with simulations.

The overlay for this one is here:

The official version of the paper can be found on arXiv here and the Fediverse announcement here:

https://fediscience.org/@OJ_Astro/115932387870297108

Next, and last for this week, we have “The Kinematic Properties of TŻO Candidate HV 11417 with Gaia DR3” by Anna J. G. O’Grady (Carnegie Mellon University, USA). This was published on Wednesday 21st January 2026 in the folder Solar and Stellar Astrophysics. This work uses updated data to confirm that HV 11417, a potential Thorne-Żytkow Object, is probably part of the Small Magellanic Cloud and qualifies as a runaway star.

The overlay is here:

The official version can be found on arXiv here and the Fediverse announcement is here:

https://fediscience.org/@OJ_Astro/115932444483985982

That concludes the update for this week. I will do another next Saturday.

#angularBispectrum #arXiv250105422v3 #arXiv251123368v2 #AstridSimulations #AstrophysicsOfGalaxies #bispectrum #CosmologyAndNonGalacticAstrophysics #DiamondOpenAccess #DiamondOpenAccessPublishing #GaiaDR3 #largeScaleStructureOfTheUniverse #LittleRedDots #OpenAccess #OpenAccessPublishing #OpenJournalOfAstrophysics #SolarAndStellarAstrophysics #TheOpenJournalOfAstrophysics #ThorneŻytkowObjects

Weekly Update from the Open Journal of Astrophysics – 17/01/2026

It’s Saturday once more so time for another update of activity at the Open Journal of Astrophysics. Since the last update we have published seven papers, bringing the number in Volume 9 (2026) to 11 and the total so far published by OJAp up to 459. This week has been quite busy; for only the second time in recorded history we published at least one paper each working day.

I will continue to include the announcements made on our Mastodon account (on Fediscience) to encourage you to visit it. Mastodon is a really excellent service, and a more than adequate replacement for X/Twitter which nobody should be using.

The first three papers this week were all published on Monday January 12th in the folder Astrophysics of Galaxies.

The first paper to report this week is “Rotational Kinematics in the Globular Cluster System of M31: Insights from Bayesian Inference” by Yuan (Cher) Li & Brendon J. Brewer (U. Auckland, New Zealand), Geraint F. Lewis (U. Sydney, Australia) and Dougal Mackey (independent researcher, Australia). This study uses Bayesian modelling to explore the kinematics of globular clusters in the Andromeda Galaxy, revealing distinct rotation patterns that suggest different subgroups were added at separate times.

The overlay is here:

You can find the officially accepted version on arXiv here and the announcement on Fediverse here:

https://fediscience.org/@OJ_Astro/115881522738421378

The second paper is “DESI Data Release 1: Stellar Catalogue” by Sergey Koposov (U. Edinburgh, UK) and an international cast of 67 other authors. This paper introduces and describes the stellar Value-Added Catalogue (VAC) based on DESI Data Release 1, providing measurements for over 4 million stars, including radial velocity, abundance, and stellar parameters.

The overlay for this one is here:

The official version of the paper can be found on arXiv here and the Fediverse announcement here:

https://fediscience.org/@OJ_Astro/115881586884465975

Next we have “On the origins of oxygen: ALMA and JWST characterise the multi-phase, metal-enriched, star-bursting medium within a ‘normal’ z>11 galaxy” by Joris Witstok (Cosmic Dawn Centre, Copenhagen, Denmark) and 37 others in locations dotted around the world. This paper presents new ALMA observations of the JADES-GS-z11-0 galaxy confirm the presence of the [O III] 88 µm line, suggesting it consists of two low-mass components undergoing star formation and enriched in metals.

The overlay is here:

The official version can be found on arXiv here and the Fediverse announcement is here:

https://fediscience.org/@OJ_Astro/115881659633273777

The fourth paper this week is also in the folder Astrophysics of Galaxies. but was published on Tuesday 13th January. It is entitled “Accelerated calibration of semi-analytic galaxy formation models” by Andrew Robertson and Andrew Benson (Carnegie Observatories, USA). This paper presents a faster calibration framework for galaxy formation models, using fewer simulations for each evaluation. However, the model shows discrepancies suggesting the model needs to be made more flexible.

The overlay is here:

You can find the officially accepted version on arXiv here and the Mastodon announcement here:

https://fediscience.org/@OJ_Astro/115887131054018297

Next one up, published on Wednesday 14th January in the folder Cosmology and Nongalactic Astrophysics, is “Constraints from CMB lensing tomography with projected bispectra” by Lea Harscouet & David Alonso (U. Oxford), UK), Andrina Nicola (U. Manchester, UK) and Anže Slosar (Brookhaven National Laboratory, USA). This study presents angular power spectra and bispectra of DESI luminous red galaxies, finding that the galaxy bispectrum can constrain the amplitude of matter fluctuations and the non-relativistic matter fraction. The overlay is here:

You can find the officially accepted paper on arXiv here and the Mastodon announcement here:

https://fediscience.org/@OJ_Astro/115893813149036197

The sixth paper this week is “Universal numerical convergence criteria for subhalo tidal evolution” by Barry T. Chiang & Frank C. van den Bosch (Yale U., USA) and Hsi-Yu Schive (National Taiwan University, Taiwan). This was published on Thursday 15th January in the folder Cosmology and Nongalactic Astrophysics; it presents an analysis of a simulation suite that addresses the ‘overmerging’ problem in cosmological simulations of dark matter subhalos, showing that up to 50% of halos in state-of-the art simulations are unresolved. The overlay is here:

The final accepted version of this paper can be found on arXiv here. The Mastodon announcement follows:

https://fediscience.org/@OJ_Astro/115898339098021093

Finally for this week we have “Detectability of dark matter subhalo impacts in Milky Way stellar streams” by Junyang Lu , Tongyan Lin & Mukul Sholapurkar (UCSD, USA) and Ana Bonaca (Carnegie Observatories, USA). This was published on Friday 16th January (i.e. yesterday) in the folder Astrophysics of Galaxies. The study develops a method to estimate the minimum detectable dark matter subhalo mass in stellar streams, ranking them by sensitivity and identifying promising lines for further research.

The overlay is here:

The officially accepted version can be found on arXiv here and the Fediverse announcement here:

https://fediscience.org/@OJ_Astro/115904083514716420

That concludes the update for this week. I will do another next Saturday.

#ALMA #arXiv250207781v3 #arXiv250514787v3 #arXiv250707968v2 #arXiv250722888v4 #arXiv250900143v2 #arXiv251026901v2 #arXiv260105380v2 #AstrophysicsOfGalaxies #BayesianMethods #CosmologyAndNonGalacticAstrophysics #DarkEnergySurvey #darkMatter #DES #DiamondOpenAccess #DiamondOpenAccessPublishing #galaxyFormation #JWST #M31 #MilkyWay #OpenAccess #OpenAccessPublishing #OpenJournalOfAstrophysics #Oxygen #semiAnalyticModels #subhalos #TheOpenJournalOfAstrophysics #Tomography #weakGravitationalLensing

Weekly Update from the Open Journal of Astrophysics – 10/01/2026

Welcome to the first proper update for 2026 from the Open Journal of Astrophysics. The New Year brings us to Volume 9. In many countries, especially in Europe, Christmas is celebrated on January 6th so this week was also affected by the holiday season. Nevertheless, since the last update we have published four papers, bringing the number in Volume 9 (2026) to 4 and the total so far published by OJAp up to 452.

The first paper this week (and of course the first of 2026) is “A targeted, parallax-based search for Planet Nine” by Hector Socas-Navarro and Ignacio Trujillo (both of the Instituto de Astrofísica de Canaria, Spain). This article describes a targeted search for the hypothesized Planet Nine in the outer solar system, using parallax position shifts. No credible candidates were found within the observed field. It was published on Tuesday January 6th in the folder Earth and Planetary Astrophysics. The overlay is here:

You can find the officially accepted version on arXiv here and the announcement on Fediverse here:

https://fediscience.org/@OJ_Astro/115847068676034973

The second paper is “Going beyond S8: fast inference of the matter power spectrum from weak-lensing surveys” by Cyrille Doux (Université Grenoble Alpes, France) and Tanvi Karwal (U. Chicago, USA). This was published on Wednesday January 7th in the folder Cosmology and Nongalactic Astrophysics and it presents a new framework to extract the scale-dependent matter power spectrum from cosmic shear and CMB lensing measurements, revealing a consistent suppression in the matter power spectrum in galaxy-lensing. The overlay is here:

The official version of the paper can be found on arXiv here and the Fediverse announcement here:

https://fediscience.org/@OJ_Astro/115853112748106265

Next we have “Constraining the Stellar-to-Halo Mass Relation with Galaxy Clustering and Weak Lensing from DES Year 3 Data” which is led by G. Zacharegkas et al. (Argonne National Laboratory, USA) and has 102 other authors too numerous to list by name from many institutions around the world again too numerous to list by name. It presents a framework to analyze the relationship between a galaxy’s stellar mass and its dark matter halo mass, using data from the Dark Energy Survey. The findings align with previous results. This paper was published on Thursday January 8th in the folder Astrophysics of Galaxies. The overlay is here:

The official version can be found on arXiv here and the Fediverse announcement is here:

https://fediscience.org/@OJ_Astro/115858972601709198

Finally for this week we have “Distance measurements from the internal dynamics of globular clusters: Application to the Sombrero galaxy (M 104)” by Katja Fahrion (University of Vienna, Austria) and 9 others based in Spain, Australia, UK, USA, Brazil, Germany and Switzerland. This was published on Friday 9th January (yesterday) in the folder Astrophysics of Galaxies. This study uses the globular cluster velocity dispersion method to measure the distance to the Sombrero galaxy, finding it to be approximately 9.0 Mpc away. The overlay is here:

The officially accepted version can be found on arXiv here and the Fediverse announcement here:

https://fediscience.org/@OJ_Astro/115864438724623861

That concludes the update for this week. I will do another next Saturday.

#arXiv250405473v2 #arXiv250616434v3 #arXiv250622367v3 #AstrophysicsOfGalaxies #CosmologyAndNonGalacticAstrophysics #DarkEnergySurvey #DES #DiamondOpenAccess #DiamondOpenAccessPublishing #EarthAndPlanetaryAstrophysics #galaxyClustering #galaxyHalo #OpenAccess #OpenAccessPublishing #OpenJournalOfAstrophysics #Planet9 #PowerSpectrum #StellarMass #TheOpenJournalOfAstrophysics #weakGravitationalLensing

Not a Weekly Update from the Open Journal of Astrophysics – 03/01/2026

Not entirely surprisingly, we have not published any papers at the Open Journal of Astrophysics since the last update on 27th December 2025. Of course many authors have been on holiday and there were no arXiv announcements on either Tuesday 30th December or Thursday 1st January anyway. Although we had a few papers accepted before the break, none of them appeared this past week. I dare say some of them will appear next week. We will be starting Volume 9 in 2026, as soon as there is a paper to publish in it.

There bing no papers to report, instead of doing one of the regular Saturday updates, I’d like to take the opportunity afforded by this pause to thank everyone who has supported the Open Journal of Astrophysics this year – Editors, Reviewers, Authors and the excellent Library staff at Maynooth University Library – and who have made it such a bumper year. I’d also like to repeat a call for volunteers to join the Editorial Board. In 2023 we published just 50 papers, and in 2025 the figure was 213, so we have more than quadrupled in two years. How many will we publish in 2026?

Here is a graphic showing the number of new papers submitted to the Open Journal of Astrophysics since January 2020:

As the legend explains, this is only the first submission of a paper – resubmissions of revised papers are not included. You can see the thicket is getting denser all the time!

The increasing number of articles is of course very welcome indeed, but it is increasing the load on our Editorial Board many of whom are also very busy with other things. We have expanded the Board recently, but we’re always for volunteers to join the team, in any area of astrophysics. As a reminder, here are the areas we cover, corresponding to the sections of astro-ph on the arXiv:

• astro-ph.GA – Astrophysics of Galaxies. Phenomena pertaining to galaxies or the Milky Way. Star clusters, HII regions and planetary nebulae, the interstellar medium, atomic and molecular clouds, dust. Stellar populations. Galactic structure, formation, dynamics. Galactic nuclei, bulges, disks, halo. Active Galactic Nuclei, supermassive black holes, quasars. Gravitational lens systems. The Milky Way and its contents
• astro-ph.CO – Cosmology and Nongalactic Astrophysics. Phenomenology of early universe, cosmic microwave background, cosmological parameters, primordial element abundances, extragalactic distance scale, large-scale structure of the universe. Groups, superclusters, voids, intergalactic medium. Particle astrophysics: dark energy, dark matter, baryogenesis, leptogenesis, inflationary models, reheating, monopoles, WIMPs, cosmic strings, primordial black holes, cosmological gravitational radiation
• astro-ph.EP – Earth and Planetary Astrophysics. Interplanetary medium, planetary physics, planetary astrobiology, extrasolar planets, comets, asteroids, meteorites. Structure and formation of the solar system
• astro-ph.HE – High Energy Astrophysical Phenomena. Cosmic ray production, acceleration, propagation, detection. Gamma ray astronomy and bursts, X-rays, charged particles, supernovae and other explosive phenomena, stellar remnants and accretion systems, jets, microquasars, neutron stars, pulsars, black holes
• astro-ph.IM – Instrumentation and Methods for Astrophysics. Detector and telescope design, experiment proposals. Laboratory Astrophysics. Methods for data analysis, statistical methods. Software, database design
• astro-ph.SR – Solar and Stellar Astrophysics. White dwarfs, brown dwarfs, cataclysmic variables. Star formation and protostellar systems, stellar astrobiology, binary and multiple systems of stars, stellar evolution and structure, coronas. Central stars of planetary nebulae. Helioseismology, solar neutrinos, production and detection of gravitational radiation from stellar systems.

We are looking for experienced scientists in any of these areas, and it would indeed be useful to have people who can cover a range of subjects (as some of our existing editors do). Since we don’t charge authors or readers we can not offer payment to Editors but it is nevertheless a way of providing a service to the community. If you’re interested, please get in touch either through the Open Journal website here, through a message on Mastodon here or BlueSky here.

#DiamondOpenAccess #DiamondOpenAccessPublishing #EditorialBoard #OpenJournalOfAstrophysics #TheOpenJournalOfAstrophysics

Weekly Update from the Open Journal of Astrophysics – 27/12/2025

I wasn’t planning to do another update this week but I thought it would be best to complete the publications for 2025  at the Open Journal of Astrophysics, so that I don’t have to do a bigger update in the new year, and I have a bit of time this morning, so here we go.

Since the last update we have published four papers which brings the number in Volume 8 (2025) up to 201. Adding the 12 papers in the Supplement, this brings the final total for the year up to 213, and the total so far published by OJAp up to 448. In 2023 we published just 50 papers, so we have more than quadrupled in two years.

The first paper this week is “Transverse Velocities in Real-Time Cosmology: Position Drift in Relativistic N-Body Simulations” by Alexander Oestreicher (University of Southern Denmark), Chris Clarkson (QMUL, UK), Julian Adamek (Universität Zürich, CH) and Sofie Marie Koksbang (U. Southern Denmark). This study uses a general relativistic N-body simulation code to explore how cosmological structures affect position drift measurements, a new method for studying cosmic structure formation and velocity fields. This was published on Tuesday 23rd December 2025 in the folder Cosmology and Nongalactic Astrophysics.

The overlay is here:

You can find the officially accepted version on arXiv here and this is the announcement on Mastodon (Fediscience):

Open Journal of Astrophysics

@[email protected]

New Publication at the Open Journal of Astrophysics: "Transverse Velocities in Real-Time Cosmology: Position Drift in Relativistic N-Body Simulations" by Alexander Oestreicher (University of Southern Denmark), Chris Clarkson (QMUL, UK), Julian Adamek (Universität Zürich, CH) and Sofie Marie Koksbang (U. Southern Denmark)

https://doi.org/10.33232/001c.154744

The second paper of the week is “On the statistical convergence of N-body simulations of the Solar System” by Hanno Rein, Garett Brown and Mei Kanda (U. Toronto, Canada). This study presents numerical experiments to determine the minimum timestep for long-term simulations of the Solar System, finding that timesteps up to 32 days yield physical results.  It was published on Tuesday December 23rd in the folder Earth and Planetary Astrophysics.

The overlay is here:

You can find the official version of this one on arXiv here. The federated announcement on Mastodon is here:

Open Journal of Astrophysics

@[email protected]

New Publication at the Open Journal of Astrophysics: "On the statistical convergence of N-body simulations of the Solar System" by Hanno Rein, Garett Brown and Mei Kanda (U. Toronto, Canada)

https://doi.org/10.33232/001c.154745

Next, published on 24th December 2025 in the folder High-Energy Astrophysical Phenomena, we have “The explosion jets of the core-collapse supernova remnant Circinus X-1” by Noam Soker and Muhammad Akashi (Technion, Haifa, Israel). This paper suggests that the rings in the Circinus X-1 supernova remnant resulted from jet-driven explosions, supporting the jittering-jets explosion mechanism theory for core collapse supernovae.

The overlay is here:

The officially accepted paper can be found on arXiv here and the announcement on Mastodon is here

Open Journal of Astrophysics

@[email protected]

New Publication at the Open Journal of Astrophysics: "The explosion jets of the core-collapse supernova remnant Circinus X-1" by Noam Soker and Muhammad Akashi (Technion, Haifa, Israel)

https://doi.org/10.33232/001c.154770

Finally for 2025 we have “Quantifying the Fermi paradox via passive SETI: a general framework” by Matthew Civiletti (City University of New York, USA). This was published on Wednesday 24th December in the folder Instrumentation and Methods for Astrophysics. The author uses SETI observations and the Drake Equation to calculate the probability of detecting at least one extraterrestrial signal, highlighting the model’s limitations and potential improvements. The overlay is here:

The officially accepted version can be found on arXiv here and the Mastodon announcement here:

Open Journal of Astrophysics

@[email protected]

New Publication at the Open Journal of Astrophysics: "Quantifying the Fermi paradox via passive SETI: a general framework" by Matthew Civiletti (City University of New York, USA)

https://doi.org/10.33232/001c.154771

And that concludes the updates for 2025. I’ll be back in a week with the first update of 2026, which will include the first paper(s) of Volume 9.

I’d like to thank everyone who has supported the Open Journal of Astrophysics this year – Editors, Reviewers, Authors and the excellent Library staff at Maynooth – and who have made it such a bumper year. In 2023 we published just 50 papers, so we have more than quadrupled in two years. How many will we publish in 2026?

#arXiv250500062v2 #arXiv250704987v2 #arXiv250810843v2 #arXiv251005956v2 #CircinusX1 #coreCollapseSupernovae #Cosmology #CosmologyAndNonGalacticAstrophysics #DiamondOpenAccess #DiamondOpenAccessPublishing #EarthAndPlanetaryAstrophysics #FermiParadox #HighEnergyAstrophysicalPhenomena #OpenAccess #OpenJournalOfAstrophysics #SETI #SolarSystem #Stability #TheOpenJournalOfAstrophysics #TransverseVelocities

Weekly Update from the Open Journal of Astrophysics – 20/12/2025

Christmas is coming, but it’s still time for the usual update of the week’s new papers at the Open Journal of Astrophysics. Since the last update we have published two more regular papers, described below, which brings the number in Volume 8 (2025) up to 197, as well as the 12 papers in yesterday’s Supplement, and the total published for the year up to 209, and the total so far published by OJAp up to 444.

Please note that we will be pausing publishing activity from 24th December 2025 until Monday 5th January 2026. Submissions will remain open, but no more papers will be published in Volume 8 (2025) after Christmas Eve. We will resume in the New Year with Volume 9.

Now for this week’s update. Since I blogged about the contents of the Supplement yesterday I won’t repeat them here and will instead just include the two regular papers.

The first regular paper this week is “Optimal intrinsic alignment estimators in the presence of redshift-space distortions” by Claire Lamman (Harvard-Smithsonian CfA, USA), Jonathan Blazek (Ohio State U., USA) and Daniel J. Eisenstein (Northeastern U., USA). This was published on Monday December 15th 2025 in the folder  Cosmology and Nongalactic Astrophysics. The authors present estimators for quantifying intrinsic alignments in large spectroscopic surveys intended to inprove the constraints they provide for weak gravitational lensing and other cosmological applications.

The overlay is here:

You can find the officially accepted version on arXiv here and this is the announcement on Mastodon (Fediscience):

Open Journal of Astrophysics

@[email protected]

New Publication at the Open Journal of Astrophysics: "Optimal intrinsic alignment estimators in the presence of redshift-space distortions" by Claire Lamman (Harvard-Smithsonian CfA), Jonathan Blazek (Ohio State U.) and Daniel J. Eisenstein (Northeastern U.); all based in the USA

https://doi.org/10.33232/001c.154373

The second regular paper of the week is “What is the contribution of gravitational infall on the mass assembly of star-forming clouds? A case study in a numerical simulation of the interstellar medium” by Noé Brucy (Universite Claude Bernard Lyon 1, France), Enrique Vázquez-Semadeni (Universidad Nacional Autónoma de México, Mexico), Tine Colman (Universite Claude Bernard Lyon 1, France), Jérémy Fensch (Universite Claude Bernard Lyon 1, France) and Ralf S. Klessen (Universität Heidelberg, Germany). This was published in the folder Astrophysics of Galaxies on Friday 19th December 2025. This paper describes research using numerical simulations to quantify how much of the mass inflow into a star-forming cloud is driven by the self-gravity of the gas and the gravity from the stellar disk.

The overlay is here:

You can find the official version of this one on arXiv here. The federated announcement on Mastodon is here:

Open Journal of Astrophysics

@[email protected]

New Publication at the Open Journal of Astrophysics: "What is the contribution of gravitational infall on the mass assembly of star-forming clouds? A case study in a numerical simulation of the interstellar medium" by Noé Brucy (Universite Claude Bernard Lyon 1, France), Enrique Vázquez-Semadeni (Universidad Nacional Autónoma de México, Mexico), Tine Colman (Lyon), Jérémy Fensch (Lyon) and Ralf S. Klessen (Universität Heidelberg, Germany)

https://doi.org/10.33232/001c.154637

And that concludes the update for this week, which will be the last Saturday update for 2025.

#arXiv250416076v3 #arXiv251009480v2 #AstrophysicsOfGalaxies #CosmologyAndNonGalacticAstrophysics #DiamondOpenAccess #DiamondOpenAccessPublishing #gravitationalInfall #InterstellarMedium #intrinsicAlignments #OpenAccess #OpenJournalOfAstrophysics #RedshiftSpaceDistortions #starFormation #starFormingClouds #TheOpenJournalOfAstrophysics #weakGravitationalLensing

Supplement to the Open Journal of Astrophysics – “Pulsar Science with the SKAO”

It’s been a busy day at the Open Journal of Astrophysics as we’ve published 12 related papers in the form of our first ever Supplement; officially it is Vol. 8 Supplement Issue 1. The idea of a Supplement is to publish a set of related papers together. I imagine it might be of interest for publishing conference proceedings, etc.

The topic of this Supplement is Pulsar Science with the Square Kilometre Array Observatory and it includes updates to the Science Case for the SKAO, the previous version of which is 10 years old. All the papers are indendependently peer-reviewed, which took some organizing and a lot of time because many potential referees are themselves members of the SKA Pulsar Science Working Group! Anyway, the final versions of all the papers hit the arXiv this morning so I published them all today.

Rather than include all 12 papers in tomorrow’s Saturday update I decided just to show the overlay for the overview of the special issue, which is here:

The following paragraph describes the content of the supplement and includes links to the other 11 papers in the issue.

The large instantaneous sensitivity, a wide frequency coverage and flexible observation modes with large number of beams in the sky are the main features of the upcoming SKA observatory’s two telescopes, the SKA-Low and the SKA-Mid, which are located on two different continents. Owing to these capabilities, the SKAO telescopes are going to be a game-changer for radio astronomy in general and pulsar astronomy in particular. The eleven articles in this special issue on pulsar science with the SKA Observatory describe its impact on different areas of pulsar science. Phase 1 of the rollout of the SKAO telescope is likely to double the known pulsar population in new surveys described in the first three papers (Keane et al. 2025; Abbate et al. 2025; Bagchi et al. 2025). These new discoveries will improve our understanding of the dynamics, evolution and gas content of globular clusters and the black hole at the centre of the Milky Way galaxy apart from increasing the samples for each of different kinds of radio emitting neutron stars (Levin et al. 2025). The larger population sample will enhance our understanding of the magneto-ionic interstellar medium (Tiburzi et al. 2025; Xu et al. 2025), the pulsar magnetosphere (Oswald et al. 2025) and pulsar wind nebulae (Gelfand et al. 2025). Moreover, the discovery of exotic neutron star systems will test gravity theory ever more stringently (Krishnan et al. 2025) and will probe fundamental physics at sub-atomic level (Basu et al. 2025). Finally, this enhanced sample is likely to make the sky portrait sharper in nano-Hertz gravitational waves impacting on our understanding of the Universe in a fundamental way (Shannon et al. 2025). In summary, the papers in this special issue describe the way the upcoming SKA Observatory’s telescopes address fundamental physics through the study of pulsars and gravitational waves.

#DiamondOpenAccessPublishing #OpenAccessPublishing #OpenJournalOfAstrophysics #PulsarScience #pulsars #SKAO #SquareKilometreArray #SquareKilometreArrayObservatory #TheOpenJournalOfAstrophysics

Weekly Update from the Open Journal of Astrophysics – 13/12/2025

It’s time once again for the usual Saturday morning update of the week’s new papers at the Open Journal of Astrophysics. Since the last update we have published a further five papers, which brings the number in Volume 8 (2025) up to 195, and the total so far published by OJAp up to 430.

The first paper this week is “Cosmic Rays Masquerading as Cool Cores: An Inverse-Compton Origin for Cool Core Cluster Emission” by Philip F. Hopkins (Caltech), Eliot Quataert (Princeton), Emily M. Silich, Jack Sayers, Sam B. Ponnada and Isabel S. Sands (Caltech).  This was published on Tuesday 9th December 2025 in the folder marked High-Energy Astrophysical Phenomena. It presents an argument  that cosmic-ray inverse-compton emission could contribute significantly to the X-ray surface brightness (SB) in cool-corre clusters, implying that gas densities may have been overestimated therein.

The overlay is here:

You can find the officially accepted version on arXiv here and the Fediverse announcement is here:

Open Journal of Astrophysics

@[email protected]

New Publication at the Open Journal of Astrophysics: "Cosmic Rays Masquerading as Cool Cores: An Inverse-Compton Origin for Cool Core Cluster Emission" by

Philip F. Hopkins (Caltech), Eliot Quataert (Princeton), Emily M. Silich, Jack Sayers, Sam B. Ponnada and Isabel S. Sands (Caltech)

https://doi.org/10.33232/001c.154053

The second paper of the week is “Detecting False Positives With Derived Planetary Parameters: Experimenting with the KEPLER Dataset” by Ayan Bin Rafaih (Aitchison College, Lahore, Pakistan) and Zachary Murray (Université Côte d’Azur, France). This one was published on 9th December 2025 in the folder Earth and Planetary Astrophysics. It is an investigation into the performance of a range of machine-learning algorithms on the KEPLER dataset, using precision-recall trade-off and accuracy metrics.

The overlay is here:

You can find the official version of this one on arXiv here. The federated announcement on Mastodon is here:

Open Journal of Astrophysics

@[email protected]

New Publication at the Open Journal of Astrophysics: "Detecting False Positives With Derived Planetary Parameters: Experimenting with the KEPLER Dataset" by Ayan Bin Rafaih (Aitchison College, Lahore, Pakistan) and Zachary Murray (Université Côte d’Azur, France)

https://doi.org/10.33232/001c.154054

Next one up is “The role of peculiar velocity uncertainties in standard siren cosmology” by Chris Blake and Ryan J. Turner (Swinburne, Australia). This paper discusses the impact of peculiar velocities on the error in H0 determinations from local distance indicators with observed redshifts, incorporating the effect of bulk flows. It was published on Tuesday 9th December in the folder Cosmology and Nongalactic Astrophysics.

The overlay is here:

You can find the official accepted version on arXiv here. The fediverse announcement is here:

Open Journal of Astrophysics

@[email protected]

New Publication at the Open Journal of Astrophysics: "The role of peculiar velocity uncertainties in standard siren cosmology" by Chris Blake and Ryan J. Turner (Swinburne, Australia)

https://doi.org/10.33232/001c.154055

The fourth article of the week is “Transient QPOs of Fermi-LAT blazars with Linearly Multiplicative Oscillations” by P. Penil (Clemson University, USA) and 7 others based in the USA, Italy and Germany. This was published on Thursday 10th December in the folder High-Energy Astrophysical Phenomena. This paper presents an investigation of patterns of quasi-periodic oscillations in observed blazar systems characterized by periodic multiplicative amplitudes including both the periodicities and long-term variations.  The overlay is here:

You can find the official published version on arXiv here. The Fediverse announcement follows:

Open Journal of Astrophysics

@[email protected]

New Publication at the Open Journal of Astrophysics: "Transient QPOs of Fermi-LAT blazars with Linearly Multiplicative Oscillations" by P. Penil (Clemson University, USA) and 7 others based in the USA, Italy and Germany

https://doi.org/10.33232/001c.154123

The last paper for this week is “Tidally Delayed Spin-Down of Very Low Mass Stars” by Ketevan Kotorashvili and Eric G. Blackman (U. Rochester, USA). This was published on Friday 12th December (yesterday) in the folder Solar and Stellar Astrophysics. It discusses the effect of tides from sub-stellar companions on rotational evolution of very low-mass stars, suggesting that these may explain the dearth of field, late-type M dwarfs with intermediate rotation periods.

The overlay is here:

You can find the officially-accepted version on arXiv here, and the Mastodon announcement is here:

Open Journal of Astrophysics

@[email protected]

New Publication at the Open Journal of Astrophysics: "Tidally Delayed Spin-Down of Very Low Mass Stars" by Ketevan Kotorashvili and Eric G. Blackman (U. Rochester, USA)

https://doi.org/10.33232/001c.154268

And that concludes the update for this week. I will do another of these regular announcements next Saturday, which will be the last such update for 2025. Will we make it past 200 for the year? Tune in next week to find out!

#arxiv241117916v3 #arxiv250713906v3 #arxiv250718712v2 #arxiv250813801v2 #arxiv250903101v2 #blazars #coolCoreClusters #cosmicRays #cosmologyAndNongalacticAstrophysics #diamondOpenAccess #diamondOpenAccessPublishing #earthAndPlanetaryAstrophysics #fermiLat #highEnergyAstrophysicalPhenomena #kepler #machineLearning #openAccess #openAccessPublishing #openJournalOfAstrophysics #peculiarMotions #quasiPeriodicOscillations #solarAndStellarAstrophysics #standardSirens #theOpenJournalOfAstrophysics #tidalSpinDown #transientAstronomy #veryLowMassStars

Weekly Update from the Open Journal of Astrophysics – 06/12/2025

Once again it’s time for the usual Saturday morning update of the week’s new papers at the Open Journal of Astrophysics. Since the last update we have published a further six papers, which brings the number in Volume 8 (2025) up to 190, and the total so far published by OJAp up to 425. I blogged about the significance of the latter figure here.

The first paper this week is “The galaxy-IGM connection in THESAN: observability and information content of the galaxy-Lyman-alpha cross-correlation at z>6” by Enrico Garaldi (U. Tokyo, Japan), Verena Bellscheidt (Tech. U. Munich, Germany), Aaron Smith (U. Texas Austin, USA) and Rahul Kannan (York U. Canada). This paper was published on Monday 1st December 2025 in the folder Cosmology and Nongalactic Astrophysics. It describes an investigation of the impact of observational limitations on the ability to retrieve the intrinsic galaxy-Lyman-alpha cross correlation from line-of-sight observations.

The overlay is here:

You can find the officially accepted version on arXiv here and the Fediverse announcement is here:

Open Journal of Astrophysics

@[email protected]

New Publication at the Open Journal of Astrophysics: "The galaxy-IGM connection in THESAN: observability and information content of the galaxy-Lyman-alpha cross-correlation at z>6" by Enrico Garaldi (U. Tokyo, Japan), Verena Bellscheidt (Tech. U. Munich, Germany), Aaron Smith (U. Texas Austin, USA) and Rahul Kannan (York U. Canada)

https://doi.org/10.33232/001c.151666

The second paper of the week is “A Less Terrifying Universe? Mundanity as an Explanation for the Fermi Paradox” by Robin H.D. Corbet (U. Maryland, USA). This paper was published on 1st December 2025 in the folder Instrumentation and Methods for Astrophysics. It presents a discussion of possible explanations for the lack of s evidence for the presence of technology-using extraterrestrial civilizations in the Galaxy (usually called the Fermi paradox). The overlay is here:

You can find the official version of this one on arXiv here. The federated announcement on Mastodon is here:

Open Journal of Astrophysics

@[email protected]

New Publication at the Open Journal of Astrophysics: "A Less Terrifying Universe? Mundanity as an Explanation for the Fermi Paradox" by Robin H.D. Corbet (U. Maryland, USA)

https://doi.org/10.33232/001c.151454

Next one up is “Sulphur abundances in star-forming regions from optical emission lines: A new approach based on photoionization models consistent with the direct method” by Enrique Pérez-Montero, Borja Pérez-Díaz, & José M. Vílchez ( (Instituto de Astrofísica de Andalucía, Spain), Igor A. Zinchenko (LMU, Germany), Asier Castrillo, Marta Gavilán, Sandra Zamora & Ángeles I. Díaz (Universidad Autonoma de Madrid, Spain). This was published on 1st December 2025 in the folder Astrophysics of Galaxies. This study uses the emission lines produced in the optical part of the spectrum and with photoionization models to derive sulphur chemical abundances in the gas-phase of star-forming galaxies.

The overlay is here:

You can find the official accepted version on arXiv here. The fediverse announcement is here:

Open Journal of Astrophysics

@[email protected]

New Publication at the Open Journal of Astrophysics: "Sulphur abundances in star-forming regions from optical emission lines: A new approach based on photoionization models consistent with the direct method" by Enrique Pérez-Montero, Borja Pérez-Díaz, & José M. Vílchez ( (Instituto de Astrofísica de Andalucía, Spain), Igor A. Zinchenko (LMU, Germany), Asier Castrillo, Marta Gavilán, Sandra Zamora & Ángeles I. Díaz (Universidad Autonoma de Madrid , Spain)

https://doi.org/10.33232/001c.151253

The fourth article of the week is “Bayesian Posteriors with Stellar Population Synthesis on GPUs” by Georgios Zacharegkas & Andrew Hearin (Argonne National Laboratory, USA) and Andrew Benson (Carnegie Observatories, USA). This is an exploration of a range of computational techniques aimed at accelerating Stellar Population Synthesis predictions of galaxy photometry using the JAX library to target GPUs (Graphics Processing Units, in case you didn’t know). This paper was published on Tuesday December 2nd 2025 in the folder Astrophysics of Galaxies.

The overlay is here:

You can find the official published version on arXiv here. The Fediverse announcement follows:

Open Journal of Astrophysics

@[email protected]

New Publication at the Open Journal of Astrophysics: "Bayesian Posteriors with Stellar Population Synthesis on GPUs" by Georgios Zacharegkas & Andrew Hearin (Argonne National Laboratory, USA) and Andrew Benson (Carnegie Observatories, USA)

https://doi.org/10.33232/001c.151255

Next one up is “IAEmu: Learning Galaxy Intrinsic Alignment Correlations” by Sneh Pandya Yuanyuan Yang, Nicholas Van Alfen, Jonathan Blazek and Robin Walters (Northeastern University, Boston, USA). This presents a neural-network-based emulator that predicts the galaxy position-position, position-orientation, and orientation-orientation, correlation functions and their uncertainties using mock catalogs based on the halo occupation distribution (HOD) framework. It was published on December 2nd 2025 in the folder Cosmology and Nongalactic Astrophysics. The overlay is here:

The official accepted version can be found on arXiv here. The Mastodon announcement is here:

Open Journal of Astrophysics

@[email protected]

New Publication at the Open Journal of Astrophysics: "IAEmu: Learning Galaxy Intrinsic Alignment Correlations" by Sneh Pandya Yuanyuan Yang, Nicholas Van Alfen, Jonathan Blazek and Robin Walters (Northeastern University, Boston, USA)

https://doi.org/10.33232/001c.151749

The last paper for this weel is “Unraveling the Nature of the Nuclear Transient AT2020adpi” by Paarmita Pandey (Ohio State University, USA) and a team of 15 others based in the USA, UK and Australia. This was published on Thursday December 4th 2025 in the folder High-Energy Astrophysical Phenomena. It is an investigation into a particular transient event AT2020adpi and a discussion of whether it is an extreme example of AGN variability or a Tidal Disruption Event (TDE). The overlay is here:

You can find the officially-accepted version on arXiv here, and the Mastodon announcement is here:

Open Journal of Astrophysics

@[email protected]

New Publication at the Open Journal of Astrophysics: "Unraveling the Nature of the Nuclear Transient AT2020adpi" by Paarmita Pandey (Ohio State University, USA) and 15 others based in the USA, UK and Australia

https://doi.org/10.33232/001c.151453

And that concludes the update for this week. I will do another next Saturday.

#arxiv241002850v2 #arxiv250405235v4 #arxiv250614736v2 #arxiv250619919v2 #arxiv250903593v3 #arxiv250922878v2 #astrophysicsOfGalaxies #at2020adpi #bayesianMethods #cosmologyAndNongalacticAstrophysics #diamondOpenAccessPublishing #fermiParadox #gpus #highEnergyAstrophysicalPhenomena #instrumentationAndMethodsForAstrophysics #intrinsicAlignments #lymanAlpha #machineLearning #nuclearTransient #openAccessPublishing #openJournalOfAstrophysics #photoionization #seti #starFormation #stellarPopulations #suplhur #theOpenJournalOfAstrophysics #thesanSimulations

Like a Million Pounds…

I’ve come down with some sort of lurgy and had to cancel a tutorial that was due to take place today, which I am sorry about. I did, however, manage to rise from my sick bed earlier this morning to publish a paper at the Open Journal of Astrophysics. When I checked the publishing dashboard I saw that this one is paper No. 425. This is a significant figure if you reckon by the cost of an Article Processing Charge (APC) at Monthly Notices of the Royal Astronomical Society. The current APC is £2356 per paper. If you multiply this by 425 the result is just over a million pounds (£1,001,300 to be exact). The Open Journal of Astrophysics, being a Diamond Open Access journal, is totally free for authors.

I mentioned a couple of weeks ago, that this is a small fraction of the money being wasted by the astronomical community worldwide on publication charges but if even a small operation like ours can save a million pounds, just think of what could happen if we all published this way! For one thing, there would certainly be more money available for actual research. That doesn’t only go for astronomy, of course: almost every scientific discipline is being ripped off by publishers who have hijacked the Open Access movement to generate income from APCs.

I’ll repeat the quotation I posted yesterday about a scandal relating to corporate publishing giant Elsevier

The scandal exposes the windfall profits of scientific publishers, who in recent years have amassed billions of dollars in earnings from public funds earmarked for science.

It’s a shocking idea, I know, but what if we spent public funds on what they are supposed to be spent on rather than handing millions to greedy publishers?

#apc #articleProcessingCharge #diamondOpenAccess #mnras #monthlyNoticesOfTheRoyalAstronomicalSociety #openAccess #openJournalOfAstrophysics #theOpenJournalOfAstrophysics

Eight Years in Maynooth…

Today is 1st December 2025, which means that it’s eight years to the day since I started work at Maynooth University. Despite the frustrations, I’m still very happy I made the move all that time ago.

We’ve now had more than a year since the merger of the former Departments of Theoretical and Experimental Physics. This has gone pretty well, actually, with significant improvements in terms of some steps forward in rationalising teaching. It does, however, feel less like a merger and more like an acquisition, with the theoretical activity effectively subsumed into the old Experimental Physics department. I suppose that was inevitable given the relative sizes of the two former Departments, but it has led to a loss of identity and the loss of the group spirit we use to have in Theoretical Physics. To add to this a number of familiar faces have left – two of my own PhD students, Aonghus Hunter-McCabe and Aoibhinn Gallagher have graduated and left, as have others with different supervisors. I am delighted for their success, of course, but will miss having them around.

I continue to enjoy teaching, and was pleasantly surprised to continue doing the same modules this academic year as last. The big change in that regard has been the adoption of different assessment methods to deal with the possibility of students using AI to do their coursework. That seems to be going reasonably well, though I’ll have to wait until the January examinations to see the outcomes.

The thing I’m probably most proud of over the past eight years is, with the huge help of staff at Maynooth University Library, getting the Open Journal of Astrophysics off the ground and attracting some excellent papers. This year has seen yet more significant growth, publications this year set to reach 200, after 120 in 2024 and just 50 the year before that (2024). We’re still smaller than many of the mainstream astrophysics journals, but we’re still growing…

Anyway, eight years of service mean that only two remain until I can claim the full state pension. I’ll be retiring as soon as I can afford to. There were Open Days at Maynooth on Friday and Saturday (28th and 29th November, respectively). These were for prospective students to enter in September 2026. Since I don’t teach any first or second year Physics modules now, and that is likely to continue, it looks like I’ll never see any of that intake in class.

#genai #maynooth #theOpenJournalOfAstrophysics

Weekly Update from the Open Journal of Astrophysics – 29/11/2025

It’s Saturday again, so it’s time for the usual update of the week’s new papers at the Open Journal of Astrophysics. Publishing this week was interrupted by the Thanksgiving holiday in the United States, which meant there were no arXiv announcements yesterday. Nevertheless, since the last update we have published another four papers, which brings the number in Volume 8 (2025) up to 184, and the total so far published by OJAp up to 419.

The first paper this week is “A theoretical prediction for the dipole in nearby distances using cosmography” by Hayley J. Macpherson (U. Chicago, USA) and Asta Heinesen (Niels Bohr Institute, Denmark). This was published on Monday 24th November 2025 in the folder Cosmology and Nongalactic Astrophysics. It presents a method to predict the dipole in luminosity distances that arises due to nearby inhomogeneities to leading-order correction to the standard isotropic distance-redshift law. Incidentally, I wrote about a talk by one of the authors here.

The overlay is here:

You can find the officially accepted version on arXiv here and the Fediverse announcement is here:

Open Journal of Astrophysics

@[email protected]

New Publication at the Open Journal of Astrophysics: "A theoretical prediction for the dipole in nearby distances using cosmography" by Hayley J Macpherson (U. Chicago, USA) and Asta Heinesen (Niels Bohr Institute, Denmark)

https://doi.org/10.33232/001c.150319

The second paper of the week is “A Targeted Gamma-Ray Search of Five Prominent Galaxy Merger Systems with 17 years of Fermi-LAT Data” by Siddhant Manna and Shantanu Desai (IIT Hyderabad Kandi, India). This one was published on Tuesday November 25th 2025 in the folder marked High-Energy Astrophysical Phenomena. It describes a search for gamma-ray emission in Fermi-LAT data from five merging galaxy systems with marginal detections for two of them

The overlay is here:

You can find the official version of this one on arXiv here. The federated announcement on Mastodon is here:

Next one up is “Metallicity fluctuation statistics in the interstellar medium and young stars – II. Elemental cross-correlations and the structure of chemical abundance space” by Mark R. Krumholz (ANU, Australia), Yuan-Sen Ting (Ohio State U., USA), Zefeng Li (Durham U., UK), Chuhan Zhang (ANU), Jennifer Mead (Columbia U., USA) and Melissa K. Ness (ANU). This was published in the folder Astrophysics of Galaxies on Wednesday November 26th. It presents an extended stochastically-forced diffusion model for the chemical evolution of galaxies, making quantitative predictions for the degree of correlation in abundance patterns in both gas and young stars.

The overlay is here:

You can find the official accepted version on arXiv here. The fediverse announcement is here:

Open Journal of Astrophysics

@[email protected]

New Publication at the Open Journal of Astrophysics: "Metallicity fluctuation statistics in the interstellar medium and young stars – II. Elemental cross-correlations and the structure of chemical abundance space" by Mark R. Krumholz (ANU, Australia), Yuan-Sen Ting (Ohio State U., USA), Zefeng Li (Durham U., UK), Chuhan Zhang (ANU), Jennifer Mead (Columbia U., USA) and Melissa K. Ness (ANU)

https://doi.org/10.33232/001c.150356

The fourth and final paper of the week is “Simulating realistic Lyman-alpha emitting galaxies including the effect of radiative transfer” by Hasti Khoraminezhad & Shun Saito (Missouri Institute of Science & Technology, USA), Max Gronke (U. Heidelberg, Germany) and Chris Byrohl (MPA Garching, Germany). An empirical model for Lyman-alpha emitters (LAEs) which provides predictions for the halo occupation distributions and relationship between luminosity and halo mass, including the distribution of satellite LAEs. It was published on Thursday November 27th 2025 in the folder Astrophysics of Galaxies.

The overlay is here:

You can find the official published version on arXiv here. The Fediverse announcement follows:

Open Journal of Astrophysics

@[email protected]

New Publication at the Open Journal of Astrophysics: "Simulating realistic Lyman-alpha emitting galaxies including the effect of radiative transfer" by Hasti Khoraminezhad & Shun Saito (Missouri Institute of Science & Technology, USA), Max Gronke (U. Heidelberg, Germany) and Chris Byrohl (MPA Garching, Germany)

https://doi.org/10.33232/001c.151254

And that concludes the update for this week. I will do another next Saturday.

#arxiv250701095v3 #arxiv250714572v2 #arxiv250716707v2 #arxiv250806232v2 #astrophysicsOfGalaxies #chemicalAbundances #cosmography #cosmology #cosmologyAndNongalacticAstrophysics #diamondOpenAccess #diamondOpenAccessPublishing #fermiLat #galaxyMergers #gammaRay #highEnergyAstrophysicalPhenomena #lymanAlphaEmitters #metallicity #openAccess #openAccessPublishing #openJournalOfAstrophysics #theOpenJournalOfAstrophysics

Weekly Update from the Open Journal of Astrophysics – 22/11/2025

It’s Saturday again, so it’s time for the usual update of the week’s new papers at the Open Journal of Astrophysics. Since the last update we have published another five papers, which brings the number in Volume 8 (2025) up to 180, and the total so far published by OJAp up to 415.

The first paper to report this week is “Probing Anisotropic Cosmic Birefringence with Foreground-Marginalised SPT B-mode Likelihoods” by Lennart Balkenhol (Sorbonne Université, France), A. Coerver (UC Berkeley, USA), C. L. Reichardt (U. Melbourne, Australia) and J. A. Zebrowski (U. Chicago, USA). This paper was published on Monday November 17th in the folder Cosmology and Nongalactic Astrophysics. It presents a way of using data from the Souh Pole Telescope (SPT) in the CMB-lite framework to constrain the level of cosmic birefringence.  The overlay is here:

You can find the officially accepted version on arXiv here and the The Fediverse announcement is here:

Open Journal of Astrophysics

@[email protected]

New Publication at the Open Journal of Astrophysics: "Probing Anisotropic Cosmic Birefringence with Foreground-Marginalised SPT B-mode Likelihoods" by Lennart Balkenhol (Sorbonne Université, France), A. Coerver (UC Berkeley, USA), C. L. Reichardt (U. Melbourne, Australia) and J. A. Zebrowski (U. Chicago, USA)

https://doi.org/10.33232/001c.147459

The second paper of the week is “Radio Observations of a Candidate Redback Millisecond Pulsar: 1FGL J0523.5-2529” by Owen. A. Johnson & E. F. Keane (Trinity College Dublin, Ireland), D. J. McKenna (ASTRON, NL), H. Qiu (SKAO, UK), S. J. Swihart (Insitute for Defense Analyses, USA), J. Strader (Michigan State U., USA) and M. McLaughlin (West Virginia U., USA). This one was published on Tuesday November 18th 2025 in the folder marked High-Energy Astrophysical Phenomena and it describes a search for radio emission from a candidate “redback pulsar” J0523.5-2529 resulting in upper limits but no detection.

The overlay is here:

You can find the official version of this one on arXiv here. The federated announcement on Mastodon is here:

Open Journal of Astrophysics

@[email protected]

New Publication at the Open Journal of Astrophysics: "Radio Observations of a Candidate Redback Millisecond Pulsar: 1FGL J0523.5-2529" by Owen. A. Johnson & E. F. Keane (Trinity College Dublin, Ireland), D. J. McKenna (ASTRON, NL), H. Qiu (SKAO, UK), S. J. Swihart (Insitute for Defense Analyses, USA), J. Strader (Michigan State U., USA) and M. McLaughlin (West Virginia U., USA)

https://doi.org/10.33232/001c.147516

Next one up is “The role of turbulence in setting the phase of the ISM and implications for the star formation rate” by Tine Colman (Université Paris-Saclay, France) and 13 others based in France, Germany, Italy and the UK. This was published in the folder Astrophysics of Galaxies on Tuesday November 18th. It descrtibes using a suite of stratified box simulations to explore the link between star formation, turbulence and the thermal state of the multi-phase interstellar medium (ISM).

The overlay is here:

You can find the official accepted version on arXiv here. The fediverse announcement is here:

Open Journal of Astrophysics

@[email protected]

New Publication at the Open Journal of Astrophysics: "The role of turbulence in setting the phase of the ISM and implications for the star formation rate" by Tine Colman (Université Paris-Saclay, France) and 13 others based in France, Germany, Italy and the UK.

https://doi.org/10.33232/001c.147517

The fourth paper of the week is “A Bimodal Metallicity Distribution Function in the Ultra-Faint Dwarf Galaxy Reticulum II” by Alice M. Luna (U. Chicago, USA) and 8 others based in the USA, Korea and Canada. This was published on Wednesday November 19th in the folder Astrophysics of Galaxies. It decribes low-resolution Magellan/IMACS spectroscopy of 167 stars in the ultra-faint galaxy Reticulum II, revealing a clearly bimodal distribution.

The overlay is here:

You can find the official published version on arXiv here. The Fediverse announcement follows:

Open Journal of Astrophysics

@[email protected]

New Publication at the Open Journal of Astrophysics: "A Bimodal Metallicity Distribution Function in the Ultra-Faint Dwarf Galaxy Reticulum II" by Alice M. Luna (U. Chicago, USA) and 8 others based in the USA, Korea and Canada.

https://doi.org/10.33232/001c.147696

The fifth and final paper for this week is “Cool Gas in the Circumgalactic Medium of Massive Post Starburst Galaxies” by Zoe Harvey, Sahyadri Krishna, Vivienne Wild & Rita Tojeiro (U. St Andrews, UK) and Paul Hewett (U. Cambridge, UK). This was published on Thursday November 20th in the folder Astrophysics of Galaxies.

The overlay is here:

The officially accepted version can be found on arXiv here. The Fediverse announcement is here:

Open Journal of Astrophysics

@[email protected]

New Publication at the Open Journal of Astrophysics: "Cool Gas in the Circumgalactic Medium of Massive Post Starburst Galaxies" by Zoe Harvey, Sahyadri Krishna, Vivienne Wild & Rita Tojeiro (U. St Andrews, UK) and Paul Hewett (U. Cambridge, UK)

https://doi.org/10.33232/001c.147836

And that concludes the update for this week. I will do another next Saturday.

#arxiv250303305v4 #arxiv250616462v2 #arxiv250622287v3 #arxiv250815435v2 #arxiv251007928v2 #astrophysicsOfGalaxies #cosmicBirefringence #cosmicMicrowaveBackground #cosmologyAndNongalacticAstrophysics #diamondOpenAccess #diamondOpenAccessPublishing #highEnergyAstrophysicalPhenomena #interstellarMedium #openAccess #openJournalOfAstrophysics #polarization #redbackPulsar #reticulumIi #spectroscopy #theOpenJournalOfAstrophysics #turbulence #ultraFaintDwarfGalaxy

Visiting Speaker

I’ve been playing host today to my former PhD student, now at the University of Vienna, Mateja Gosenca, who gave a talk on “Ultralight Dark Matter: Phenomenology and Observational Constraints”. Mateja did an MSc at the University of Sussex before doing a PhD under my supervision, so it is very nice to have her visit us in Maynooth.

It was only when I started to think about how to introduce her Colloquium that I remembered that Mateja was co-author of the very first paper published by the Open Journal of Astrophysics, way back in 2016. At that time we were running an experimental prototype site before switching to the Scholastica platform we now use, but it was still a landmark. We’ve now published 415 papers.

Update: Obligatory pub photograph

#matejaGosenca #maynoothUniversity #theOpenJournalOfAstrophysics

Weekly Update from the Open Journal of Astrophysics – 04/10/2025

It’s Saturday again, so it’s time for a summary of the week’s new papers at the Open Journal of Astrophysics. Since the last update we have published five more papers, which brings the number in Volume 8 (2025) up to 146, and the total so far published by OJAp up to 381. At this rate Volume 8 will contain around 190 by the end of 2025.

Anyway, here are this week’s papers, starting with three published on Monday 29th September 2025.

The first paper is “Cosmic Multipoles in Galaxy Surveys II: Comparing Different Methods in Assessing the Cosmic Dipole” by Vasudev Mittal, Oliver T. Oayda and Geraint F. Lewis (U. Sydney, Australia). This is in the folder Cosmology and Nongalactic Astrophysics. It presents a comparison of methods for determining the number count dipole from cosmological surveys with a discussion of the implications for the known discordance with the CMB diple.

The overlay is here:

You can make this larger by clicking on it.  The officially accepted version of this paper can be found on the arXiv here.

The second paper this week, also published on Monday 29th September, is “SDSS-C4 3028: the Nearest Blue Galaxy Cluster Devoid of an Intracluster Medium” by Shweta Jain (University of Kentucky, USA) and 11 others based in the USA, Australia and Korea. This describes a galaxy cluster with an unusually high fraction (about 63%) of star-forming galaxies which may be a result of ram pressure stripping; the article is in the folder Astrophysics of Galaxies.

The corresponding overlay is here:

You can find the officially accepted version on arXiv here.

The third one this week, published on also published on Monday 29th September but in the folder Earth and Planetary Astrophysics, is “Comparing the Architectures of Multiplanet Systems from Kepler, K2, and TESS Data” by Robert L Royer and Jason H. Steffen (University of Nevada, USA).  This paper explores the trends seen in exoplanet survey data, including Kepler, TESS, and K2 including many planetary systems with multiple planets.

The overlay is here:

You can find the officially-accepted version on arXiv here.

The next one up is “Seeding Cores: A Pathway for Nuclear Star Clusters from Bound Star Clusters in the First Billion Years” by Fred Angelo Batan Garcia (Columbia University, USA), Massimo Ricotti (University of Maryland, USA) and Kazuyuki Sugimura (Hokkaido University, Japan). This paper was published on Thursday 2nd October in the folder Astrophysics of Galaxies. This is about modelling the formation of Nuclear Star Clusters using cosmological radiation-hydrodynamic simulations, with discussion of the implications for seeding supermassive black holes and the little red dots seen by JWST.

The corresponding overlay is here:

You can find the officially accepted version of this one on arXiv here.

The fifth and last one for this week, published on Friday 3rd October 2025, is “Efficient semi-analytic modelling of Pop III star formation from Cosmic Dawn to Reionization” by Sahil Hegde and Steven R. Furlanetto (University of Californi Los Angeles, USA).  This is also in the folder marked Astrophysics of Galaxies. It uses a self-consistent analytic model to trace the formation of the first stars from their birth through the first billion years of the universe’s history. complementing semi-analytic and computational methods.

You can find the officially-accepted version of this paper on arxiv here.

That concludes the report for this week. I’ll post another update next Saturday.

#arXiv250308779v2 #arXiv250620654v3 #arXiv250719581v2 #arXiv250920651v1 #arXiv250922523v1 #AstrophysicsOfGalaxies #cosmicDipoles #CosmologyAndNonGalacticAstrophysics #DiamondOpenAccess #EarthAndPlanetaryAstrophysics #GalaxyCluster #galaxyFormation #galaxySurveys #JWST #Kepler #LittleRedDots #MultiplanetSystems #nuclearStarClusters #OpenAccessPublishing #OpenJournalOfAstrophysics #PopulationIIIStars #ramPressureStripping #SDSSC42028 #semiAnalyticGalaxyFormation #TheOpenJournalOfAstrophysics

Weekly Update from the Open Journal of Astrophysics – 06/09/2025

It’s Saturday again, so it’s time for a summary of the week’s new papers at the Open Journal of Astrophysics. Since the last update we have published two new papers, which brings the number in Volume 8 (2025) up to 127, and the total so far published by OJAp up to 362. It’s been another relatively slow week, not least because of the Labor (sic) Day holiday in the USA on Monday which, among other things, meant there was no arXiv update on Tuesday.

Anyway, the first paper to report this week is “An analytical model for the dispersion measure of Fast Radio Burst host galaxies” by Robert Reischke, Michael Kovač & Andrina Nicola (U. Bonn, Germany), Steffen Hagstotz (Ludwig-Maximilians Universität München) and Aurel Schneider (U. Zurich, Switzlerland). This is a theoretical study of the dispersion measures (DMs) intrinsic to host galaxies of Fast Radio Burst (FRB) sources to enable separation of that from the line-of-sight DM. This one was published on Monday 1st September 2025 in the folder Cosmology and NonGalactic Astrophysics.

The overlay is here:

You can make this larger by clicking on it.  The officially accepted version of this paper can be found on the arXiv here.

The second paper this week, published on Wednesday 3rd Sepember in the folder Solar and Stellar Astrophysics, is “Complex spectral variability and hints of a luminous companion in the Be star + black hole binary candidate ALS 8814” by Kareem El-Badry (Caltech, USA), Matthias Fabry (Villanova U., USA), Hugues Sana (KU Leuven, Belgium), Tomer Shenar (Tel Aviv U., Israel) and Rhys Seeburger (MPA Heidelberg, Germany).

The overlay for this one is here:

You can find the officially accepted version on arXiv here.

And that’s all the papers for this week. It’s still a bit slow as we emerge from the summer vacations, we have a lot of papers in the pipeline that I expect to emerge pretty soon.

#arXiv241117682v2 #arXiv250901545v1 #BeStar #BlackHoleBinary #CosmologyAndNonGalacticAstrophysics #DiamondOpenAccess #DiamondOpenAccessPublishing #DispersionMeasures #fastRadioBursts #OpenJournalOfAstrophysics #SolarAndStellarAstrophysics #TheOpenJournalOfAstrophysics

Weekly Update from the Open Journal of Astrophysics – 30/08/2025

Once again it’s time for a summary of the week’s new papers at the Open Journal of Astrophysics. Since the last update we have published three new papers, which brings the number in Volume 8 (2025) up to 125, and the total so far published by OJAp up to 360.

The first paper to report this week is “Large-scale surveys of the quasar proximity effect” by Rupert Croft, Patrick Shaw & Ann-Marsha Alexis (Carnegie Mellon University; CMU), Nianyi Chen (Princeton), Yihao Zhou & Tiziana Di Matteo (CMU), Simeon Bird (UC Riverside), Patrick Lachance (CMU), and Yueying Ni (Harvard). This paper was published on Monday 25th August in the folder Cosmology and NonGalactic Astrophysics. It presents a CDM-based halo model of the quasar proximity effect, tested on quasar Lyman-alpha spectra from the ASTRID cosmological simulation, including self-consistent formation of quasar black holes and the intergalactic medium.

The overlay is here:

You can make this larger by clicking on it, as you can with all the overlays below. The officially accepted version of this paper can be found on the arXiv here.

The second paper this week, also published on Monday 25th August, but in the folder Astrophysics of Galaxies, is “Redshift evolution of Lyman continuum escape fraction after JWST” by Andrea Ferrara (Pisa), M. Giavalisco (UMass Amherst), L. Pentericci (Rome), E. Vanzella (Bologna), A. Calabrò (Rome) and M. Llerena (Rome). This paper is about the Attenuation-Free Model (AFM) for galaxies, in which radiation-driven outflows develop once the galaxy specific star formation rate exceeds a certain level, which is tested on data with positive results. The overlay is here:

You can find the officially accepted version on arXiv here.

The third and final paper this week is “Primordial black holes in cosmological simulations: growth prospects for supermassive black holes” by Lewis R Prole, John A Regan, Daxal Mehta & Peter Coles (National University of Ireland, Maynooth) and Pratika Dayal (Groningen, NL). This one was published in Astrophysics of Galaxies folder on Thursday 28th August 2025. You can read more about this paper here: basically it studies the growth of primordial black holes in the early Universe using numerical simulations, with implications for the subsequent formation of massive black holes.

The overlay is here:

You can find the officially accepted version of this one on arXiv here.

And that’s all the papers for this week. It’s still a bit slow as we emerge from the summer vacations, but I expect things will start to pick up from now on.

#arXiv250403848v2 #arXiv250510619v2 #arXiv250611233v2 #AstrophysicsOfGalaxies #AttenuationFreeModel #CosmologyAndNonGalacticAstrophysics #DiamondOpenAccess #DiamondOpenAccessPublishing #JWST #LymanContinuum #massiveBlackHoles #OpenJournalOfAstrophysics #primordialBlackHoles #ProximityEffect #quasars #TheOpenJournalOfAstrophysics

EAS 2025 in Cork

Tomorrow I’ll be travelling to the fine city of Cork, where I shall be for most of next week, attending the 2025 Annual Meeting of the European Astronomical Society I was planing to travel today, but I have some things to attend to at home tomorrow morning so I won’t get to Cork until late afternoon.

The EAS Annual Meeting is a very large meeting with well over a thousand participants expected. It is held each year in a different European city but, according to tradition, never a capital. Last year it was in Padova (Italy) and the year before that in Kraków (Poland).

I usually enjoy smaller-scale meetings and workshops over these mega-conferences, but I’m looking forward to this one. There will be a strong Maynooth contingent there but I also hope to see some old friends from elsewhere, as well as catching up on some exciting science results.

Talking of science, I am on the Scientific Organizing Committee for this meeting. The programme is very large and diverse and there were a few headaches on the way, but nothing compared to the logistical challenges facing the local organizers; they will probably reach peak stress levels ahead of the opening of the meeting, but I’m sure everything will go well. The Irish National Astronomy Meeting (INAM) was actually held in Cork in 2023. Although a much smaller meeting than EAS, the experience of running that will probably have helped the organizers.

I’m not actually giving a talk at EAS but I will be participating in a panel discussion in a special session on The Future of Scientific Publishing: Strategies and Challenges for Astronomy on Tuesday 24th June. When I saw the initial announcement for this special session, I was was concerned that it would be entirely dominated by representatives of the journal Astronomy & Astrophysics and their publisher EDP Sciences. The first session (9.00 to 10.30) titled “SCIENCE PUBLISHING TODAY AND TOMORROW” is still like that, but the panel discussion in the second session (13.15 to 14.45) “SCIENCE PUBLISHING: A COMMUNITY’S VIEW” is a bit more balanced than that, with a representatives of NASA/ADS and the European Southern Observatory (among others). If I’m given an opportunity to get a word in, I’ll be arguing that traditional journals are unnecessary and obsolete.

#Cork #EAS2025 #EuropeanAstronomicalSociety #OpenJournalOfAstrophysics #TheOpenJournalOfAstrophysics

Weekly Update from the Open Journal of Astrophysics – 14/06/2025

It’s Saturday so once again it’s time for the weekly update of papers published at the Open Journal of Astrophysics. Since the last update we have published two new papers, which brings the number in Volume 8 (2025) up to 71, and the total so far published by OJAp  is now up to 306.

The two papers published this week, with their overlays, are as follows. You can click on the images of the overlays to make them larger should you wish to do so.

The first paper to report is “Analysis of optical spectroscopy and photometry of the type I X-ray bursting system UW CrB2” by Mark Kennedy (University College Cork, Ireland) and 21 others based in Ireland, UK, USA, Finland, Netherlands and Australia. This one was published on Tuesday June 10th in the folder High-Energy Astrophysical Phenomena.  This describes optical photometry and spectroscopy of the low-mass X-ray binary UW Coronae Borealis taken over 2 years

The overlay is here:

You can read the final accepted version on arXiv here.

The second paper is “The Impact of Feedback-driven Outflows on Bar Formation” by Martin D. Weinberg (University of Massachusetts, Amherst, USA). This paper uses a generalization of the Hamiltonian Mean-Field model to of the disruption of bar formation in galaxies by stellar feedback. It was published on Friday 13th June 2025 in the folder marked Astrophysics of Galaxies.

The overlay is here:

You can find the officially-accepted version of the paper on arXiv here.

That’s all the papers for this week. I’ll post another update next weekend.

#arXiv240312138v2 #arXiv240806404v2 #Astrophysics #AstrophysicsOfGalaxies #BarFormationInGalaxies #DiamondOpenAccess #HighEnergyAstrophysicalPhenomena #lowMassXRayBinary #OpenAccessPublishing #OpenJournalOfAstrophysics #StellarFeedback #TheOpenJournalOfAstrophysics #UWCoronaeBorealis

Funding Diamond Open Access

In case you weren’t aware, SciPost is a publishing infrastructure that provides Diamond Open Access to scientific papers. That means they are free to publish and free to read. They are funded by a consortium but are now struggling financially. They have recently circulated an open letter to the Community explaining their predicament and asking for help. I encourage you to read it and, if you can, to make a donation (or bully your institution to do so).

The open letter explains that SciPost is currently running at an average cost per paper of €500. That is much less than a typical APC for a mainstream journal but it is not a negligible cost. At the rate at which SciPost is publishing it amounts to about €1000 per day. SciPost currently attracts a significant level of sponsorship but it is not enough to support its current level of activity. Information on how to help SciPost can be found here. It is a worthy cause and deserves to be supported.

One area in which SciPost has not really taken of is Astronomy, where it has published very few papers. This may at be at least partly because of the Open Journal of Astrophysics (OJAp) which is also Diamond Open Access but runs in a very different and much cheaper way. A full breakdown of costs at OJAp is given here our annual running costs are about €5000 per year, which works out at less than €50 per paper (on average); that comprises a fixed component and a marginal cost of €10 per paper.

The main reasons for the large difference in running costs are: (i) SciPost maintains and runs its own platform; and (ii) it offers a copy-editing service. OJAp piggy-backs on arXiv (where most astrophysics research papers are found anyway) and expects authors to provide the final version of their own work. Neither organization pays referees or Editors. To enable it to run, SciPost employs about three staff full-time (2.9 FTE to be precise); OJAp has no employees and we keep our costs down by offering a ‘no-frills’ service. Instead of having a wide range of sponsors, we are entirely funded by Maynooth University. I am very grateful for that support, but we are run on a shoestring budget.

I have written before about what I think the future of Diamond Open Access could be like. I would like to see a range of Diamond Open Access journals offering a choice for authors and serving different sub-disciplines. Most universities nowadays have publishing operations so there could be network of federated journals, some based on arXiv and some based on other repositories and others with different models, such as SciPost. Perhaps institutions are worried about the expense but, as we have shown the actual cost, is far less than they are wasting on Article Processing Charges.

I don’t see other Diamond Open Access journals as competitors, but as allies with community-led ecosystem. I’d be more than happy to discuss how to start up such a journal on the OJAp model with anyone interested, and have already done so with some interested parties. As far as I’m concerned, the more the merrier! It is neither fair nor reasonable, however, that the expense of running a journal that serves the global astrophysics community should fall entirely on one small University in Ireland.

By all means support SciPost (and get your institutions to do likewise), but please also consider supporting OJAp. We are currently covering our costs but have no funds to make enhancements (such as a much-needed new LaTex template). If you can afford to make a donation to SciPost, then perhaps you can afford to make a donation to OJAp proportionate to our lower running costs? For example, if you give €10K to SciPost, could you give us €1K too? That amount would keep SciPost running for a day and OJAp for many months…

#DiamondOpenAccess #OJAp #OpenAccess #OpenJournalOfAstrophysics #SciPost #TheOpenJournalOfAstrophysics

The 300th Publication at the Open Journal of Astrophysics

It was on October 8th last year that we published the 200th paper at the Open Journal of Astrophysics. Today, on 29th May 2025, less than 8 months later, we have reached the 300 mark with this paper:

The authors are Eliot Quataert (Princeton, USA) and Philip F. Hopkins (Caltech, USA). We continue to have a large number of papers from authors based in the USA.

I published another two papers this morning and will include all the papers published this week (Including the 300th) in the usual weekly update on Saturday. Based on the 67 papers published so far this year and the activity in the OJAp worklow, I estimate we will publish at least 150 papers this year, which means we should reach the the 400 mark early next year.

#CosmologyAndNonGalacticAstrophysics #DiamondOpenAccessPublishing #TheOpenJournalOfAstrophysics

Weekly Update from the Open Journal of Astrophysics – 11/01/2025

Welcome to the first update of 2025 from the It’s Saturday morning once again so here’s another quick update of activity at the Open Journal of Astrophysics. For the new year we have started Volume 8. Since the last update of 2024 we have published four new papers which brings the total so far published by OJAp up to 239.

In chronological order of publication, the four papers published this week, with their overlays, are as follows. You can click on the images of the overlays to make them larger should you wish to do so.

First one up is “Weak-Lensing Shear-Selected Galaxy Clusters from the Hyper Suprime-Cam Subaru Strategic Program: I. Cluster Catalog, Selection Function and Mass–Observable Relation” by Kai-Feng Chen (MIT, USA), I-Non Chiu (National Cheng University, Taiwan), Masamune Oguri (Chiba University, Japan), Yen-Ting Lin (IAAAS, Taiwan), Hironao Miyatake (Nagoya, Japan), Satoshi Miyazaki (Nat. Astr. Obs. Japan), Surhud More (IUCAA, India), Takashi Hamana (Nat. Astr. Obs. Japan), Markus M. Rau Carnegie Mellon University, USA), Tomomi Sunayama (Steward Obs., USA), Sunao Sugiyama (U. Penn, USA), Masahiro Takada (U. Tokyo, Japan).

This paper, which was published on Monday 6th January 2025 is in the folder Cosmology and NonGalactic Astrophysics, discusses steps towards towards the extraction of cosmogical constraints from a sample of galaxy clusters selected via weak gravitational lensing

Here is a screen grab of the overlay, which includes the abstract:

You can find the officially accepted version of the paper on the arXiv here.

The second paper to announce, published on 7th January 2025 and also in the folder Cosmology and NonGalactic Astrophysics, is “Cosmology on point: modelling spectroscopic tracer one-point statistics” by Beth McCarthy Gould (Newcastle U., UK), Lina Castiblanco (Bielefeld, Germany), Cora Uhlemann (Bielefeld, Germany), and Oliver Friedrich (LMU, Germany).

You can see the overlay here:

The accepted version of this paper can be found on the arXiv here.

The third paper, published on 9th January 2025, also in the folder Cosmology and NonGalactic Astrophysics, is “Probing Environmental Dependence of High-Redshift Galaxy Properties with the Marked Correlation Function” by Emy Mons and Charles Jose (Cochin University of Science and Technology, India). This paper uses the marked two-point correlation function to measure the environmental dependence of galaxy clustering at high redshift.

Here is the overlay:

The final version accepted on arXiv is here.

Last of this quartet, also published on 9th January 2025, but in the folder Astrophysics of Galaxies is “The infrared luminosity of retired and post-starburst galaxies: A cautionary tale for star formation rate measurements” by Vivienne Wild (St Andrews, UK), Natalia Vale Asari (Universidade Federal de Santa Catarina, Brazil), Kate Rowlands (STScI, Sara L. Ellison (U. Victoria, Canada), Ho-Hin Leung (St Andrews), Christy Tremonti (U. Wisconsin-Madison, USA).

The paper proposes an extension of the semi-analytic formalism to weak lensing and thermal Sunyaev-Zeldovich (tSZ) fields directly on the full-sky, with an emphasis on higher-order correlations. The overlay is here:

You can find the official accepted version on the arXiv here.

That’s all for this week. I’ll do another update next Saturday.

#arXiv240611966v2 #arXiv240908672v2 #arXiv240918182v2 #arXiv241212573v2 #cosmicShear #CosmologyAndNonGalacticAstrophysics #DiamondOpenAccess #galaxyClustering #galaxyClusters #markedTwoPointCorrelationFunction #onePointStatistics #starFormation #starburstGalaxies #Subarau #TheOpenJournalOfAstrophysics #weakGravitationalLensing

Four New Publications at the Open Journal of Astrophysics

It’s Satuday morning once again so here’s another quick update of activity at the Open Journal of Astrophysics. Since the last update a week ago we have published  four papers, which takes the count in Volume 7 (2024) up to 114 and the total published altogether by OJAp up to 229. If we publish just one more paper between now and the end of the year, we will have published as many papers in 2024 as we have in all previous years.

Anyway, in chronological order of publication, the four papers published this week, with their overlays, are as follows. You can click on the images of the overlays to make them larger should you wish to do so.

First one up is “Star formation beyond galaxies: widespread in-situ formation of intra-cluster stars” by Niusha Ahvazi & Laura V. Sales (UC Riverside, USA), Julio F. Navarro (U. Victoria, Canada), Andrew Benson (Carnegie Obs. USA), Alessandro Boselli (Aix Marseille U., France) and Richard D’Souza (Vatican Obs.). The paper, which is in the folder marked Astrophysics of Galaxies, The paper presents a simulation-based analysis of a diffuse star forming component in galaxy clusters extending for hundreds of kiloparsecs and tracing the distribution of neutral gas in the cluster host halo.

Here is a screen grab of the overlay, which includes the abstract:

You can find the officially accepted version of the paper on the arXiv here.

The second paper to announce, published on 10th December 2024 in the folder Cosmology and NonGalactic Astrophysics, is “Cosmological Constraints from Combining Photometric Galaxy Surveys and Gravitational Wave Observatories” by E.L. Gagnon, D. Anbajagane, J. Prat, C. Chang, and J. Frieman (all of U. Chicago, USA). This article quantifies the expected cosmological information gain from combining the forecast LSST 3x2pt analysis with the large-scale auto-correlation of GW sources from proposed next-generation GW experiments.

You can see the overlay here:

The accepted version of this paper can be found on the arXiv here.

The third paper, also published on 10th December 2024, but in the folder marked Earth and Planetary Astrophysics, has the title “A potential exomoon from the predicted planet obliquity of β Pictoris b” and is written by Michael Poon, Hanno Rein, and Dang Pham all of the University of Toronto, Canada. It presents discussion, based on the β Pictoris system, of the idea that the presence of exomoons can excite misalignment between the spin and orbit axis (obliquity) in exoplanet systems

Here is the overlay

The final version accepted on arXiv is here.

Last of this quartet, published on 11th December 2024, and in the folder Cosmology and NonGalactic Astrophysics is “Map-level baryonification: Efficient modelling of higher-order correlations in the weak lensing and thermal Sunyaev-Zeldovich fields” and is by Dhayaa Anbajagane & Shivam Pandey (U. Chicago) and Chihway Chang (Columbia U.), all based in the USA.

The paper proposes an extension of the semi-analytic formalism to weak lensing and thermal Sunyaev-Zeldovich (tSZ) fields directly on the full-sky, with an emphasis on higher-order correlations. The overlay is here:

You can find the official accepted version on the arXiv here.

That’s all for this week. I’ll do another update next Saturday, and that will probably be the last one of the year. If we publish just one more paper between now and 31st December, we will have published as many papers in 2024 as we have in all previous years put together!

#arXiv231216289v2 #arXiv240304839v2 #arXiv240903822v2 #arXiv241205988v1 #AstrophysicsOfGalaxies #CosmologyAndNonGalacticAstrophysics #DiamondOpenAccess #EarthAndPlanetaryAstrophysics #exomoons #exoplanets #galaxySurveys #starFormation #TheOpenJournalOfAstrophysics #thermalSunyaevZeldovichEffect

Reaching Nelson

This morning I published another paper at the Open Journal of Astrophysics and in the process I noticed that took us to a total 111 articles this year. I got to thinking about the significance of that number in cricket, where it goes by the name of Nelson…

In cricket – at least in England – Nelson is supposed to be an unlucky number. The reason for this could well be that the number 111 looks like a set of stumps without the bails (see left). (For those of you not up with the lingo, the bails are two smaller bits of wood that sit on top of the stumps. ) The absence of the bails could mean that they have been dislodged, signifying that a batter is out. Also umpires remove the bails at close of play, so it could indicate that the match is over.

What’s less clear is the connection with Horatio, Lord Nelson (right). The version I was told at school was that Nelson had “one eye, one arm, and one Trafalgar”. Some also say “Destiny” instead of “Trafalgar”. Those are polite versions. Others say the third one refers to a part of the male anatomy. Bill Frindall used to say “one eye, one arm, and one et cetera“. Who knows which, if any, of these is right?

In any case this does give me the chance to point out that, contrary to popular myth, Nelson didn’t lose an eye anyway. In 1794, Nelson was in action at the Siege of Calvi during the Invasion of Corsica when a cannonball struck a nearby sandbag and sprayed him with sand and gravel. Nelson’s right eye was damaged by this, but he didn’t lose it although he had little effective vision through it thereafter.

#111 #cricket #LordNelson #Nelson #SiegeOfCalvi #TheOpenJournalOfAstrophysics

The Future of Diamond Open Access in Astrophysics

The Open Journal of Astrophysics is now reasonably well established as a Diamond Open Access journal for the astrophysics community. We have published over a hundred articles so far this year at such a low cost that we can make our publications free to read and to publish. Thanks for all this is due to the volunteers on our Editorial Board, the excellent team at Maynooth University library, who have supported this project for 6 years, to the arXiv, as well of course to the authors who have chosen to publish with us.

Although we have established a good base, we’re still much smaller than the mainstream journals publishing just a few percent of their output. There is no sign of a slowdown at OJAp. Indeed there are signs that pace will pick up. I heard last week, for example, that Oxford University Press (the publisher of Monthly Notices of the Royal Astronomical Society) has decided to cancel the ‘Read-and-Publish’ agreement that allowed authors from Australian institutions to avoid APCs. I imagine we’ll get quite a few more submissions from Down Under thanks to that decision.

Nevertheless, we’ve a long way to go to catch up with the likes of A&A, MNRAS and ApJ in terms of numbers. If activity continues to grow then we will incur greater costs – our provider, Scholastica, charges us per paper. Those costs will still be smaller than regular journals, but I think it’s unfair that the expense of running a journal that serves the global astrophysics community should fall entirely on one small University in Ireland.

Expense is only one issue. I never envisaged that OJAp would be unique. It was more intended to be a proof of concept. I would like to see a range of Diamond Open Access journals offering a choice for authors and serving different sub-disciplines. Most universities nowadays have publishing operations so there could be network of federated journals, some based on arXiv and some based on other repositories. Perhaps institutions are worried about the expense but, as we have shown the actual cost, is far less than they are wasting on Article Processing Charges. I rather think it’s not the money that is the issue, just the unimaginatively risk-averse thinking in what passes these days for university management.

There are two simple – but not mutually exclusive – possibilities.

One is that astrophysics institutions club together and donate funds not only to keep OJAp going, but also to allow us to invest in improvements. A donation equivalent to the cost of just one APC for a typical journal would help us enormously. We do actually get some donations already, but more would always be welcome. In the long run, an investment in Diamond Open Access would pay back many times in savings; OJAp has already saved the worldwide community over £500,000.

The other is that other members of the community follow the lead of OJAp and set up their own journals. I wouldn’t see others as much as competitors, more as allies with community-led federated system. In the light of the OUP decision mentioned above, why don’t Australian research institutions set up their own version of OJAp? I’d be happy to discuss how to start up such a journal with anyone interested.

If you would like to discuss either of these possibilities please use the comment box below or email me here.

P.S. There is another issue concerning the future of OJAp, which is that I will be retiring in a few years, but now isn’t the time to discuss that one!

#DiamondOpenAccess #journals #MNRAS #OpenAccess #OpenJournalOfAstrophysics #OxfordUniversityPress #TheOpenJournalOfAstrophysics

It’s Saturday, so it’s time once again for another summary of business at the  Open Journal of Astrophysics. This week I have three papers to announce, which brings the total we have published so far this year (Vol. 7) to 98 and the total published by OJAp to 213.

First one up, published on Tuesday 29th October 2024, is “Cosmology with shear ratios: a joint study of weak lensing and spectroscopic redshift datasets” by Ni Emas & Chris Blake (Swinburne U., Australia), Rossana Ruggeri (Queensland U, Australia) and Anna Porredon (Ruhr University, Bochum, Germany). This paper is in the folder marked Cosmology and NonGalactic Astrophysics. The paper investigates the use of shear ratios as a cosmological diagnostic, with applications to lensing surveys

Here is a screen grab of the overlay, which includes the abstract:

You can read the paper directly on arXiv here.

The second paper to present, also published on Tuesday 29th October 2024, is “Echo Location: Distances to Galactic Supernovae From ASAS-SN Light Echoes and 3D Dust Maps” by Kyle D. Neumann (Penn State), Michael A. Tucker & Christopher S. Kochanek (Ohio State), Benjamin J. Shappee (U. Hawaii), and K. Z. Stanek (Ohio State), all based in the USA. This paper is in the folder marked High-Energy Astrophysical Phenomena and it presents a new approach to estimating the distance to a source by combining light echoes with recent three-dimensional dust maps with application to supernova distances.

The overlay looks like this:

You can read this paper directly on the arXiv here.

Last, but by no means least, comes  “A deconstruction of methods to derive one-point lensing statistics” by Viviane Alfradique (Universidade Federal do Rio De Janeiro, Brazil), Tiago Castro (INAF Trieste, Italy), Valerio Marra (Trieste), Miguel Quartin (Rio de Janeiro), Carlo Giocoli (INAF Bologna, Italy), and Pierluigi Monaco (Trieste).  Published in the folder marked Cosmology and NonGalactic Astrophysics, it describes a comparative study of different methods of approximating the one-point probability density function (PDF) for use in the statistical analysis of gravitational lensing.

Here is a screengrab of the overlay:

To read the accepted version of this on the arXiv please go here.

That’s it for this week. I hope to post another update next weekend, by when we might well have reached a century for this year!

https://telescoper.blog/2024/11/02/three-new-publications-at-the-open-journal-of-astrophysics-11/

#arXiv240307313v2 #arXiv240500147v2 #arXiv240714584v2 #cosmicShear #Cosmology #CosmologyAndNonGalacticAstrophysics #DiamondOpenAccess #HighEnergyAstrophysicalPhenomena #shearRatios #supernovae #TheOpenJournalOfAstrophysics #weakGravitationalLensing

A day later than has been usual for such things, it’s now time for a quick update of activity at the Open Journal of Astrophysics. This week we have published another batch of four papers which takes the count in Volume 7 (2024) up to 81 and the total published altogether by OJAp up to 196. I think there may come a week in we publish papers on every day of that week, but it was not this week…

In chronological order, the four papers published this week, with their overlays, are as follows. You can click on the images of the overlays to make them larger should you wish to do so.

First one up is “Finding the unusual red giant remnants of cataclysmic variable mergers” by Nicholas Z. Rui and Jim Fuller of California Institute of Technology (Caltech), USA. It presents a discussion of the possible photometric, astroseismological, and surface abundance signatures of red giants formed by mergers of cataclysmic variable stars. It was published on 23rd September 2024 and is in the folder marked Solar and Stellar Astrophysics.

Here is a screen grab of the overlay, which includes the abstract:

You can find the officially accepted version of the paper on the arXiv here.

The second paper to announce, also published on 23rd September 2024, is “Notes on the Practical Application of Nested Sampling: MultiNest, (Non)convergence, and Rectification” by Alexander Dittmann (U. Maryland, USA). A critical analysis of the MultiNest algorithm together with suggestions for approving its applicability. It is in the folder Instrumentation and Methods for Astrophysics.

You can see the overlay here:

The accepted version of this paper can be found on the arXiv here.

The third paper, published on 24th September 2024 in the folder marked High-Energy Astrophysical Phenomena, is called  “Merger Precursor: Year-long Transients Preceding Mergers of Low-mass Stripped Stars with Compact Objects” and is by Daichi Tsuna, Samantha Wu & Jim Fuller (Caltech), Yize Dong (UCLA) and Anthony Piro (Carnegie Observatories), all based in the USA.

Here is the overlay

The final version accepted on arXiv is here.

Last in this batch is “Spectroscopic Observations of the GALEX Nearby Young Star Survey Sample. I. Nearby Moving Group Candidates” by Navya Nagananda (Rochester, NY, USA), Laura Vican (UCLA), Ben Zuckerman (UCLA), David Rodriguez (STScI), Alexander Binks (Tübingen, Germany) & Joel Kastner (Rochester). It describes investigations of the spectra of the GALNYSS sample of over 2000 young stars and the assignment of these stars into moving groups. It is is in the folder marked Solar and Stellar Astrophysics, and was published on 25th September 2024 with this overlay:

You can find the official accepted version on the arXiv here.

That’s all for now. I will post another update in a week.

https://telescoper.blog/2024/09/29/four-new-publications-at-the-open-journal-of-astrophysics-8/

#arXiv240414474v2 #arXiv240416928v2 #arXiv240612472v2 #arXiv240915579v1 #CataclysmicVariables #DiamondOpenAccess #GALEX #HighEnergyAstrophysicalPhenomena #InstrumentationAndMethodsForAstrophysics #Multinest #OpenJournalOfAstrophysics #SolarAndStellarAstrophysics #TheOpenJournalOfAstrophysics

Once again, it’s time for a quick update of activity at the Open Journal of Astrophysics. This week we have published another batch of four papers which takes the count in Volume 7 (2024) up to 77 and the total published altogether by OJAp up to 192. Things are picking up again after the summer lull, and we’re moving towards a double century. If we keep up a steady average of four per week we’ll be at 200 per year.

In chronological order, the four papers published this week, with their overlays, are as follows. You can click on the images of the overlays to make them larger should you wish to do so.

First one up is “Quasi-two-dimensionality of three-dimensional, magnetically dominated, decaying turbulence” by Shreya Dwivedi, Chandranathan Anandavijayan, and Pallavi Bhat of TIFR, Bangalore, India. The paper presents an analysis of numerical simulations of MHD turbulence using Minkowski Functionals, with implications for local anisotropies revealed therein. It was published on 9th September 2024 and is in the folder marked High-Energy Astrophysical Phenomena.

Here is a screen grab of the overlay, which includes the abstract:

You can find the officially accepted version of the paper on the arXiv here.

The second paper to announce, also published on 9th September 2024, is “mochi_class: Modelling Optimisation to Compute Horndeski In class” by  Matteo Cataneo (Universität Bonn, Germany) and Emilio Bellini (SISSA, Trieste, Italy). This article presents a cosmological Einstein-Boltzmann solver adapted to work with Horndeski gravity, together with validation tests. It is in the folder Cosmology and NonGalactic Astrophysics.

You can see the overlay here:

The accepted version of this paper can be found on the arXiv here.

The third paper, published on 11th September 2024 in the folder marked High-Energy Astrophysical Phenomena, is by Jonathan Katz of Washington University, St Louis, USA. The title is “The Sources of Fast Radio Bursts” and it presents a discussion of the possible physical origin of Fast Radio Bursts, arguing that they fall into two distinct groups.

The final version accepted on arXiv is here.

Last in this batch, but by no means least, is “RMS asymmetry: a robust metric of galaxy shapes in images with varied depth and resolution” by Elizaveta Sazonova (U. Waterloo, Canada) with 15 other authors spread around the world (in Canada, USA, Australia, Italy, Chile, UK, Poland, Mexico, Germany, and Spain). This paper presents a method of quantifying distortion of galaxy images connected with mergers or other instabilities. It is in the folder marked Astrophysics of Galaxies and was published on September 12th 2024 with this overlay:

You can find the official accepted version on the arXiv here.

That’s all for now. I will post another update in a week.

https://telescoper.blog/2024/09/14/four-new-publications-at-the-open-journal-of-astrophysics-7/

#arXiv220713241v4 #arXiv240101965v2 #arXiv240405792v2 #arXiv240711968v2 #AstrophysicsOfGalaxies #CosmologyAndNonGalacticAstrophysics #EinsteinBoltzmannEquations #fastRadioBursts #galaxies #galaxyMergers #GalaxyShapes #HighEnergyAstrophysicalPhenomena #HorndeskiGravity #magnetohydrodynamics #MHD #MinkowskiFunctionals #OpenJournalOfAstrophysics #PlasmaPhysics #plasmaTurbulence #TheOpenJournalOfAstrophysics

It’s Saturday morning in Barcelona, and time to post another update relating to the  Open Journal of Astrophysics.  Since the last update we have published two more papers, taking  the count in Volume 7 (2024) up to 47 and the total published by OJAp up to 162. We actually accepted four papers last week, but so far only two final versions have appeared on the arXiv.

The first paper of the most recent pair – published on  Friday 14th June – is “Spectroscopic Confirmation of an Ultra-Massive Galaxy in a Protocluster at z ~ 4.9″ . The author list has a strong University of California flavour: Stephanie M. Urbano Stawinski (UC Irvine), M. C. Cooper (UC Irvine), Ben Forrest (UC Davis) , Adam Muzzin (York University, Canada), Danilo Marchesini (Tufts University), Gillian Wilson (UC Merced), Percy Gomez (Keck Observatories, USA), Ian McConachie (UC Riverside), Z. Cemile Marsan (York University, Canada), Marianna Annuziatella (Centro de Astrobiología CSIC-INTA, Spain) and Wenjun Chang (UC Riverside).

This paper presents an investigation of a cluster system involving a massive galaxy using Keck spectroscopy with determination of its redshift and star formation properties. The results pose a challenge for theorists. The paper is in the folder marked Astrophysics of Galaxies.

Here is a screen grab of the overlay which includes the abstract:

You can click on the image of the overlay to make it larger should you wish to do so. You can find the officially accepted version of the paper on the arXiv here.

The second paper, also published on Friday 14th June and has the title “Boil-off of red supergiants: mass loss and type II-P supernovae” by Jim Fuller (Caltech) and  Daichi Tsuna (Caltech, USA and University of Tokyo, Japan). This one, which is in the folder marked Solar and Stellar Astrophysics, discusses A new model for stellar mass loss which predicts that low-mass red supergiants lose less mass than commonly assumed, while high-mass red supergiants lose more.

Here is a screen grab of the overlay which includes the abstract:

You can click on the image of the overlay to make it larger should you wish to do so. You can find the officially accepted version of the paper on the arXiv here.

That concludes this week’s update. Will we reach 50 for 20204 next week? Tune in next Saturday to find out!

https://telescoper.blog/2024/06/15/two-new-publications-at-the-open-journal-of-astrophysics-11/

#arXiv240416036v3Search_ #arXiv240521049v2 #AstrophysicsOfGalaxies #galaxyClusters #KeckTelescopes #massLoss #protocluster #redSupergiants #redshift #SolarAndStellarAstrophysics #spectroscopy #stellarMassLoss #supernovae #TheOpenJournalOfAstrophysics

Time for another roundup of business at the  Open Journal of Astrophysics. This time I have three papers to announce, which brings the total we have published so far this year (Vol. 7) to 45 and the total published by OJAp to 160. We’re still on track to publish around 100 papers this year or more, compared to last year’s 50.

First one up, published on 3rd June 2024, is “Log-Normal Waiting Time Widths Characterize Dynamics” by Jonathan Katz of Washington University (St Louis, Missouri, USA). This paper presents a discussion of the connection between waiting time distributions and dynamics for aperiodic astrophysical systems, with emphasis on log-normal distributions.  This paper is in the folder marked High-Energy Astrophysical Phenomena.

Here is a screen grab of the overlay, which includes the abstract:

You can read the paper directly on arXiv here.

The second paper to present is “An Empirical Model For Intrinsic Alignments: Insights From Cosmological Simulations” by Nicholas Van Alfen (Northeastern University, Boston, USA), Duncan Campbell (Carnegie Mellon University, Pittsburgh, USA), Jonathan Blazek (Northeastern University), C. Danielle Leonard (Newcastle University, UK), Francois Lanusse (Université Paris-Saclay, France), Andrew Hearin (Argonne National Laboratory, USA), Rachel Mandelbaum (Carnegie Mellon University) and The LSST Dark Energy Science Collaboration.  This paper presents an extension of the halo model (specifically the Halo Occupation Distribution, HOD) to include intrinsic alignment effects for the study of weak gravitational lensing. This paper is in the folder marked Cosmology and Nongalactic Astrophysics. It was published on Tuesday June 4th 2024.

The overlay looks like this:

You can read this paper directly on the arXiv here.

Last, but by no means least, comes  “Towards Cosmography of the Local Universe”  which proposes the multipoles of the distance-redshift relation as new cosmological observables that have a direct physical interpretation in terms of kinematical quantities of the underlying matter flow. This was also published on 4th June. The authors are Julian Adamek (IfA Zurich, Switzerland), Chris Clarkson (Queen Mary, London, UK), Ruth Durrer (Geneva, Switzerland), Asta Heinesen (U. Lyon, France & NBI Copenhagen, Denmark), Martin Kunz (Geneva), and Hayley J. Macpherson (Chicago, USA).

Here is a screengrab of the overlay:

https://telescoper.blog/2024/06/08/three-new-publications-at-the-open-journal-of-astrophysics-9/

#aperiodicSystems #arXiv230305578v3 #arXiv231107374v2 #arXiv240212165v2 #cosmography #Cosmology #CosmologyAndNonGalacticAstrophysics #HaloModel #haloOccupationDistribution #HighEnergyAstrophysicalPhenomena #intrinsicAlignments #Lognormal #lognormalDistributions #OJAp #statistics #TheOpenJournalOfAstrophysics #waitingTimes #weakGravitationalLensing