#weak-gravitational-lensing — Public Fediverse posts

Weekly Update from the Open Journal of Astrophysics – 09/05/2026

It’s Saturday once again, so time for another update of activity at the Open Journal of Astrophysics. Since the last update we have published a further five papers, bringing the number in Volume 9 (2026) to 99 and the total so far published by OJAp up to 547. We didn’t quite make it to a hundred for the year last week, but will do so with the next paper.

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 announcements also show the DOI for each paper.

The first paper to report this week is “Formation of Close Binaries through Massive Black Hole Perturbations and Chaotic Tides” by Howard Hao-Tse Huang and Wenbin Lu (University of California at Berkeley, USA). This one was published on Wednesday 6th May 2026 in the folder Astrophysics of Galaxies. The paper presents a model of massive black hole-binary systems, showing that repeated tidal interactions can lead to the creation of hyper-velocity stars and other nuclear transients.

The overlay for this paper is here

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

https://fediscience.org/@OJ_Astro/116526323790020433

The second paper for this week, also Wednesday 6th May, but in the folder Cosmology and Nongalactic Astrophysics is “Detection of supernova magnitude fluctuations induced by large-scale structure” by Andrew Nguyen (Swinburne Institute of Technology, Australia) and 58 others based all around the world. This study uses supernovae and galaxy velocities to measure the universe’s structure growth rate, confirming the Planck LambdaCDM model prediction. The methodology is validated and shows potential for future research.

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/116526449130876366

Next one up, the third paper of the week, also published on Wednesday 6th May in the folder Cosmology and Nongalactic Astrophysics is “Comparing cosmic shear nulling methods for Stage-IV surveys” by Naomi Clare Robertson and Alex Hall (University of Edinburgh, UK). This study compares three strategies for reducing baryon feedback impact on cosmic shear measurements. All methods effectively mitigate bias, with varying degrees of efficiency and information preservation.

The overlay for this one is here:

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

https://fediscience.org/@OJ_Astro/116526251813375105

The fourth paper this week, published on Thursday May 7th, is “Egent: An Autonomous Agent for Equivalent Width Measurement” by Yuan-Sen Ting & Serat Mahmud Saad (Ohio State University, USA), Fan Liu (National Astronomical Observatories, Beijing, China), and Yuting Shen (Georgia Institute of Technology, USA). Egent is an autonomous agent that combines multi-Voigt profile fitting with large language model visual inspection for efficient, automated analysis of raw flux spectra, validated against expert measurements. This one is in the folder Instrumentation and Methods for Astrophysics. The associated software can be found here.

The overlay is here:

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

https://fediscience.org/@OJ_Astro/116531924397498394

The fifth and final article of this week was published on Friday 8th May in the folder Astrophysics of Galaxies. The title is “DiffstarPop: A generative physical model of galaxy star formation history” and it is by Alex Alarcon (Institute of Space Sciences, Barcelona, Spain), Andrew P. Hearin , Matthew R. Becker & Gillian Beltz-Mohrmann (Argonne National Laborarory, USA), and Andrew Benson & Sachi Weerasooriya (Carnegie Observatories, USA). DiffstarPop is a model that accurately and rapidly reproduces statistical distributions of galaxy star formation histories (SFH), using parameters related to galaxy formation physics.

The overlay is here:

You can find the authorized version of this paper on arXiv here and the Fediverse announcement is here:

https://fediscience.org/@OJ_Astro/116537709130989142

Here endeth this week’s update. There shall be another next Saturday.

P.S. Just a reminder that, thanks to the efforts of a member of our Editorial Board, the Open Journal of Astrophysics now has a Wikipedia page.

Weekly Update from the Open Journal of Astrophysics – 04/04/2026

It may be the Easter weekend, but it’s still time for a Saturday morning update of activity at the Open Journal of Astrophysics. Since the last update we have published a further four papers, bringing the number in Volume 9 (2026) to 71 and the total so far published by OJAp up to 519. This update coimpletes the first quarter of 2026, which suggests that if we continue to publish at the same rate we’ll reach about 280 for the year.

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 announcements also show the DOI for each paper.

The first paper to report this week is “Testing halo models for constraining astrophysical feedback with multi-probe modeling: I. 3D Power spectra and mass fractions” by Pranjal R. S. (U. Arizona, USA), Shivam Pandey Johns Hopkins U., USA), Dhayaa Anbajagane (U. Chicago, USA), Elisabeth Krause (U. Arizona) and Klaus Dolag (Max Planck Institute for Astrophysics, Germany). This paper was published on Tuesday March 31st in the folder Cosmology and Nongalactic 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/116322295318460212

The second paper for this week, also published on Tuesday March 31st in the folder Cosmology and Nongalactic Astrophysics, is “Validation of the DESI-DR1 3×2-pt analysis: scale cut and shear ratio tests” by Ni Putu Audita Placida Emas (Swinburne University of Technology, Australia) and an international cast of 56 others. This study validates the combined analysis of galaxy clustering and weak gravitational lensing data from various surveys, ensuring accurate tests of the standard cosmological model using future Stage-IV surveys

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/116322348900996677

Next one up, the third paper of the week, also published on Tuesday March 31st in the folder Cosmology and Nongalactic Astrophysics, is “Differentiable Stochastic Halo Occupation Distribution with Galaxy Intrinsic Alignments” by Sneh Pandya and Jonathan Blazek (both of Northeastern University, USA). This is a paper introducing diffHOD-IA, a differentiable model for galaxy population analysis that incorporates intrinsic alignments and halo occupation distribution. It’s validated against existing models and can be used in next-generation weak-lensing analyses.

The overlay for this one is here:

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

https://fediscience.org/@OJ_Astro/116322403314492269

The fourth and final paper this week, published on Wednesday April 1st (but not a joke), is “The Growth of Dust in Galaxies in the First Billion Years with Applications to Blue Monsters” by Desika Narayanan (U. Florida, USA) and 11 others based in the USA and Europe. This one is in the folder Astrophysics of Galaxies; it presents a simulation-based study of dust accumulation in early galaxies via supernovae production and rapid growth on tiny dust grains, with local density and grain size being important factors.

The overlay is here:

The finally accepted version of this paper can be found here and the Mastodon announcement is here:

https://fediscience.org/@OJ_Astro/116328145696781139

And that concludes the update for this week. I’ll do another next week, but I’m expecting a fairly low number of papers owing to the Easter vacation.

The KiDS Legacy

What with all the cosmological goings-on of the past couple of weeks – see here, here and here – I quite forgot to mention another important set of results. These are from the final data release Kilo-Degree Survey known as KiDS for short and represent a final analysis of the complete dataset. For those of you not in the know, KiDs is a weak lensing shear tomography survey and its core science drivers are to map the large scale matter distribution in the Universe and constrain the equation of state of Dark Energy. The results can be found in three papers on arXiv, which you can add to your reading list:

• KiDS-Legacy: Redshift distributions and their calibration (Wright et al.)
• KiDS-Legacy: Cosmological constraints from cosmic shear with the complete Kilo-Degree Survey (Wright et al.)
• KiDS-Legacy: Consistency of cosmic shear measurements and joint cosmological constraints with external probes (Stölzner et al.)

As far as I’m concerned, the main result to leap out from the cosmological analysis, which primarily constrains the clumpiness of matter in the universe, expressed by the density parameter Ωm and a fluctuation amplitude σ8 in the combined parameter “S8“, which is constrained almost independently from Ωm. The value obtained for this parameter by KiDS has previously been “in tension” with values from other experiments (notably Planck) ; see here for a discussion. The new results, however, seem consistent with the standard cosmological model. Here is a figure from the last paper in the above list that illustrates the point:

As is often the case, there’s also one of those nice Cosmology Talks videos that discusses this and other aspects of the KiDS Legacy results to which I refer you for more details!

https://www.youtube.com/watch?v=PIQKe-tW1xQ

#arXiv250319440 #arXiv250319441 #arXiv250319442 #DarEnergy #GravitationalLensing #KIDS #KiloDegreeSurvey #KilodegreeSurvey #weakGravitationalLensing

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

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

I haven’t posted anything about the European Space Agency’s Euclid mission recently but I can remedy that today by sharing a new video that describes one of the methods that Euclid will use to map the dark Universe. Here’s the video:

https://www.youtube.com/watch?v=sAP5rauEyG4

Here are the credits

Credit: ESA/Euclid Consortium/Cacao Cinema

License: ESA Standard Licence

And here’s the explainer that goes with it:

ESA’s Euclid mission is surveying the sky to explore the composition and evolution of the dark Universe. But how can Euclid see the invisible? Watch this video to learn about the light-bending effect that enables scientists to trace how dark matter is distributed in the Universe.

By making use of Euclid’s flagship simulation, the video illustrates how dark-matter filaments subtly alter the shape of galaxies. Light travelling to us from vastly distant galaxies is bent and distorted by concentrations of matter along its way. The effect is called gravitational lensing because matter (both ‘normal’ and dark matter) acts as a kind of magnifying glass.

Scientists distinguish between strong and weak gravitational lensing. In strong gravitational lensing distortions of background galaxies or other light sources are very apparent, resulting in arcs, multiple images or so-called Einstein rings. In weak lensing, background sources appear only mildly stretched or displaced. This means we can only detect this effect by analysing large numbers of sources in a statistical way.

The further we look, the more prominent the distortions from weak gravitational lensing are, because there are more dark-matter structures acting as lenses between us and the light sources.

Euclid will measure the distorted shapes of billions of galaxies over 10 billion years of cosmic history, providing a 3D view of the dark matter distribution in our Universe. This will shed light on the nature of this mysterious component.

The map of the distribution of galaxies over cosmic time will also teach us about dark energy, which affects how quickly the Universe expands. By charting the Universe’s large-scale structure in unprecedented detail, Euclid will enable scientists to trace how the expansion has changed over time.

https://telescoper.blog/2024/09/15/what-is-weak-gravitational-lensing/

#darkMatter #DarkUniverse #ESA #Euclid #EuropeanSpaceAgency #Space #weakGravitationalLensing

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

Why does #DarkMatter change the observed shape of #galaxies? 🌀 And by how much? What is #WeakGravitationalLensing and how does #ESAEuclid 🛰️ use this technique to map 📷 the matter distribution across the Universe?

We have a new @ec_euclid blog post with a brief intro into this:

👉🏻 https://www.euclid-ec.org/mapping-the-dark-universe-with-gravitational-weak-lensing

#ESA #astrodon #astronomy #space #DarkEnergy