#reionization — Public Fediverse posts

Improved Limits on the 21 cm Signal at z = 6.5–7.0 (the Epoch of #Reionization) with the Murchison Widefield Array Using Gaussian Information: https://iopscience.iop.org/article/10.3847/1538-4357/adff80 -> Astronomers hunting for evidence of the light from the first stars and galaxies have found that the Universe was warm, rather than cold, before it “lit up”: https://www.icrar.org/eor-limit/

Weekly Update from the Open Journal of Astrophysics – 16/08/2025

It’s time once again for the usual update of papers published at the Open Journal of Astrophysics which I do every Saturday. Since the last update we have published two new papers, which brings the number in Volume 8 (2025) up to 116, and the total so far published by OJAp up to 351. The summer lull we always expected is now upon us, so this will be a shorter post than we have had of late.

The first paper to report this week is “The reflex instability: exponential growth of a large-scale mode in astrophysical discs” by Aurélien Crida (Université Côte d’Azur, France), Clément Baruteau (Université de Toulouse, France), Jean-François Gonzalez (Universite Claude Bernard Lyon 1, France), Frédéric Masset (Universidad Nacional Autonoma de México) and Paul Segretain, Philippine Griveaud, Héloïse Méheut & Elena Lega (Université Côte d’Azur).  This paper was published on Tuesday August 12th 2025 in the folder marked “Earth and Planetary Astrophysics“. It discusses a exponentially-growing instability in gas discs around stars caused by the motion of the central star in response to the disc.

The overlay – which you can make larger by clicking on it – is here:

You can find the officially accepted version on arXiv here.

The other paper this week, published in the folder Cosmology and Nongalactic Astrophysics, is “The galaxy-IGM connection in THESAN: the physics connecting the IGM Lyman-alpha opacity and galaxy density in the reionization epoch” by Enrico Garaldi (University of Tokyo, Japan), Verena Bellscheidt (Technical University of Munich, Germany), Aaron Smith (York University, Canada) and Rahul Kannan (University of Texas at Dallas, USA).  It presents a study of the relation between the Lyman-alpha effective optical depth of quasar sightlines and the distribution of galaxiesas as a probe of ionized regions around sources of photons. It was published on Wednesday August 13th 2025.

The overlay is here:

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

That concludes the papers for this week. I’ll do another update next weekend, though I expect things will remain relatively quiet until September.

#arXiv241002853v2 #arXiv250807859v1 #circumstellarDisks #CosmologyAndNonGalacticAstrophysics #DiamondOpenAccess #DiamondOpenAccessPublishing #EarthAndPlanetaryAstrophysics #LymanAlphaAbsorption #OpenJournalOfAstrophysics #quasars #reionization #TheOpenJournalOfAstrophysics #THESANSimulations

Weekly Update from the Open Journal of Astrophysics – 16/08/2025

It’s time once again for the usual update of papers published at the Open Journal of Astrophysics which I do every Saturday. Since the last update we have published two new papers, which brings the number in Volume 8 (2025) up to 116, and the total so far published by OJAp up to 351. The summer lull we always expected is now upon us, so this will be a shorter post than we have had of late.

The first paper to report this week is “The reflex instability: exponential growth of a large-scale mode in astrophysical discs” by Aurélien Crida (Université Côte d’Azur, France), Clément Baruteau (Université de Toulouse, France), Jean-François Gonzalez (Universite Claude Bernard Lyon 1, France), Frédéric Masset (Universidad Nacional Autonoma de México) and Paul Segretain, Philippine Griveaud, Héloïse Méheut & Elena Lega (Université Côte d’Azur).  This paper was published on Tuesday August 12th 2025 in the folder marked “Earth and Planetary Astrophysics“. It discusses a exponentially-growing instability in gas discs around stars caused by the motion of the central star in response to the disc.

The overlay – which you can make larger by clicking on it – is here:

You can find the officially accepted version on arXiv here.

The other paper this week, published in the folder Cosmology and Nongalactic Astrophysics, is “The galaxy-IGM connection in THESAN: the physics connecting the IGM Lyman-alpha opacity and galaxy density in the reionization epoch” by Enrico Garaldi (University of Tokyo, Japan), Verena Bellscheidt (Technical University of Munich, Germany), Aaron Smith (York University, Canada) and Rahul Kannan (University of Texas at Dallas, USA).  It presents a study of the relation between the Lyman-alpha effective optical depth of quasar sightlines and the distribution of galaxiesas as a probe of ionized regions around sources of photons. It was published on Wednesday August 13th 2025.

The overlay is here:

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

That concludes the papers for this week. I’ll do another update next weekend, though I expect things will remain relatively quiet until September.

#arXiv241002853v2 #arXiv250807859v1 #circumstellarDisks #CosmologyAndNonGalacticAstrophysics #DiamondOpenAccess #DiamondOpenAccessPublishing #EarthAndPlanetaryAstrophysics #LymanAlphaAbsorption #OpenJournalOfAstrophysics #quasars #reionization #TheOpenJournalOfAstrophysics #THESANSimulations

JWST discovers how we’re able to see the Universe at all It's only because all of the neutral atoms in intergalactic space became ionized that we can see so far away through space. JWST, at last, has found who the culprit is. bigthink.com/starts-with-... #space #astronomy #jwst #reionization

JWST discovers how we're able ...

NASA’s Webb Reveals Galaxy Population Driving Cosmic Renovation ☀️✨

#Ast #Astrophysics #Galaxy #GalaxyCluster #GravitationalLensing #Reionization #SolarMagneticField #SolarMaximum

⏩ 2 new pictures and 1 new video from NASA (SVS) https://commons.wikimedia.org/wiki/Special:ListFiles?limit=14&user=OptimusPrimeBot&ilshowall=1&offset=20250612130129

NASA’s Webb Reveals Galaxy Population Driving Cosmic Renovation ☀️✨

#Ast #Astrophysics #Galaxy #GalaxyCluster #GravitationalLensing #Reionization #SolarMagneticField #SolarMaximum

⏩ 2 new pictures and 1 new video from NASA (SVS) https://commons.wikimedia.org/wiki/Special:ListFiles?limit=14&user=OptimusPrimeBot&ilshowall=1&offset=20250612130129

NASA’s Webb Reveals Galaxy Population Driving Cosmic Renovation ☀️✨

#Ast #Astrophysics #Galaxy #GalaxyCluster #GravitationalLensing #Reionization #SolarMagneticField #SolarMaximum

⏩ 2 new pictures and 1 new video from NASA (SVS) https://commons.wikimedia.org/wiki/Special:ListFiles?limit=14&user=OptimusPrimeBot&ilshowall=1&offset=20250612130129

NASA’s Webb Reveals Galaxy Population Driving Cosmic Renovation ☀️✨

#Ast #Astrophysics #Galaxy #GalaxyCluster #GravitationalLensing #Reionization #SolarMagneticField #SolarMaximum

⏩ 2 new pictures and 1 new video from NASA (SVS) https://commons.wikimedia.org/wiki/Special:ListFiles?limit=14&user=OptimusPrimeBot&ilshowall=1&offset=20250612130129

NASA’s Webb Reveals Galaxy Population Driving Cosmic Renovation ☀️✨

#Ast #Astrophysics #Galaxy #GalaxyCluster #GravitationalLensing #Reionization #SolarMagneticField #SolarMaximum

⏩ 2 new pictures and 1 new video from NASA (SVS) https://commons.wikimedia.org/wiki/Special:ListFiles?limit=14&user=OptimusPrimeBot&ilshowall=1&offset=20250612130129

Weekly Update from the Open Journal of Astrophysics – 12/04/2025

Time for the weekly Saturday morning update of papers published at the Open Journal of Astrophysics. Since the last update we have published four new papers, which brings the number in Volume 8 (2025) up to 37 and the total so far published by OJAp up to 272.

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.

The first paper to report is “Searching for new physics using high precision absorption spectroscopy; continuum placement uncertainties and the fine structure constant in strong gravity” by Chung-Chi Lee (Big Questions Institute (BQI), Sydney, Australia), John K. Webb (Cambridge, UK), Darren Dougan (BQI), Vladimir A. Dzuba & Victor V. Flambaum (UNSW, Australia) and Dinko Milaković (Trieste, Italy).

This presents a discussion of the problem of continuum placement in high-resolution spectroscopy, which impacts significantly on fine structure constant measurements, and a method for mitigating its effects. The paper is in the folder Solar and Stellar Astrophysics and was published on Tuesday 8th April 2025. The overlay is here:

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

The second paper to announce, also published on 8th April 2025,  is “Deciphering Spatially Resolved Lyman-Alpha Profiles in Reionization Analogs: The Sunburst Arc at Cosmic Noon” by Erik Solhaug (Chicago, USA), Hsiao-Wen Chen (Chicago), Mandy C. Chen (Chicago),  Fakhri Zahedy (University of North Texas),  Max Gronke (MPA Garching, Germany),  Magdalena J. Hamel-Bravo (Swinburne, Australia), Matthew B. Bayliss (U. Cincinatti), Michael D. Gladders  (Chicago), Sebastián López (Universidad de Chile), Nicolás Tejos (Universidad Católica de Valparaíso, Chile).

This paper, which presents a study of the Lyman-alpha emission properties of a gravitationally-lensed galaxy at redshift z=2.37, appears in the folder Astrophysics of Galaxies. It was published

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

The third paper of the week  is “On the progenitor of the type Ia supernova remnant 0509-67.5” by Noam Soker (Technion, Haifa, Israel). This one was published on Wednesday 9th April 2025 in the folder High-Energy Astrophysical Phenomena. The author discusses possible ideas for the origin of a supernova that exploded inside a planetary nebula.

Here is the overlay:

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

Last (but certainly) not least for this week, published on April 11th 2025, we have “Are Models of Strong Gravitational Lensing by Clusters Converging or Diverging?” by Derek Perera (U. Minnesota), John H Miller Jr & Liliya L. R. Williams (U. Minnesota, USA), Jori Liesenborgs (Hasselt U., Belgium), Allison Keen (U. Minnesota), Sung Kei Li (Hong Kong University), Marceau Limousin (Aix Marseille Univ., France).  This papers study various models of a strong gravitational lensing system, the results suggesting that lens models are neither converging to nor diverging from a common solution for this system, regardless of method.

Here is the overlay:

The official published version can be found on the arXiv here.

That’s all the papers for this week. By way of a postscript I’ll just mention that the gremlins that have affected submissions to Crossref (which we rely on for registering the article metadata) have now been resolved and normal services have been restored.

#arXiv240910604v5 #arXiv241001849v2 #arXiv241105083v2 #arXiv250304709v2 #AstrophysicsOfGalaxies #CosmicNoon #DiamondOpenAccess #DiamondOpenAccessPublishing #fineStructureConstant #HighEnergyAstrophysicalPhenomena #HighResolutionSpectroscopy #PlanetaryNebula #reionization #SolarAndStellarAstrophysics #strongGravitationalLensing #SupernovaRemnant #TheOpenJournalOfAstrophysics

Weekly Update from the Open Journal of Astrophysics – 12/04/2025

Time for the weekly Saturday morning update of papers published at the Open Journal of Astrophysics. Since the last update we have published four new papers, which brings the number in Volume 8 (2025) up to 37 and the total so far published by OJAp up to 272.

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.

The first paper to report is “Searching for new physics using high precision absorption spectroscopy; continuum placement uncertainties and the fine structure constant in strong gravity” by Chung-Chi Lee (Big Questions Institute (BQI), Sydney, Australia), John K. Webb (Cambridge, UK), Darren Dougan (BQI), Vladimir A. Dzuba & Victor V. Flambaum (UNSW, Australia) and Dinko Milaković (Trieste, Italy).

This presents a discussion of the problem of continuum placement in high-resolution spectroscopy, which impacts significantly on fine structure constant measurements, and a method for mitigating its effects. The paper is in the folder Solar and Stellar Astrophysics and was published on Tuesday 8th April 2025. The overlay is here:

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

The second paper to announce, also published on 8th April 2025,  is “Deciphering Spatially Resolved Lyman-Alpha Profiles in Reionization Analogs: The Sunburst Arc at Cosmic Noon” by Erik Solhaug (Chicago, USA), Hsiao-Wen Chen (Chicago), Mandy C. Chen (Chicago),  Fakhri Zahedy (University of North Texas),  Max Gronke (MPA Garching, Germany),  Magdalena J. Hamel-Bravo (Swinburne, Australia), Matthew B. Bayliss (U. Cincinatti), Michael D. Gladders  (Chicago), Sebastián López (Universidad de Chile), Nicolás Tejos (Universidad Católica de Valparaíso, Chile).

This paper, which presents a study of the Lyman-alpha emission properties of a gravitationally-lensed galaxy at redshift z=2.37, appears in the folder Astrophysics of Galaxies. It was published

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

The third paper of the week  is “On the progenitor of the type Ia supernova remnant 0509-67.5” by Noam Soker (Technion, Haifa, Israel). This one was published on Wednesday 9th April 2025 in the folder High-Energy Astrophysical Phenomena. The author discusses possible ideas for the origin of a supernova that exploded inside a planetary nebula.

Here is the overlay:

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

Last (but certainly) not least for this week, published on April 11th 2025, we have “Are Models of Strong Gravitational Lensing by Clusters Converging or Diverging?” by Derek Perera (U. Minnesota), John H Miller Jr & Liliya L. R. Williams (U. Minnesota, USA), Jori Liesenborgs (Hasselt U., Belgium), Allison Keen (U. Minnesota), Sung Kei Li (Hong Kong University), Marceau Limousin (Aix Marseille Univ., France).  This papers study various models of a strong gravitational lensing system, the results suggesting that lens models are neither converging to nor diverging from a common solution for this system, regardless of method.

Here is the overlay:

The official published version can be found on the arXiv here.

That’s all the papers for this week. By way of a postscript I’ll just mention that the gremlins that have affected submissions to Crossref (which we rely on for registering the article metadata) have now been resolved and normal services have been restored.

#arXiv240910604v5 #arXiv241001849v2 #arXiv241105083v2 #arXiv250304709v2 #AstrophysicsOfGalaxies #CosmicNoon #DiamondOpenAccess #DiamondOpenAccessPublishing #fineStructureConstant #HighEnergyAstrophysicalPhenomena #HighResolutionSpectroscopy #PlanetaryNebula #reionization #SolarAndStellarAstrophysics #strongGravitationalLensing #SupernovaRemnant #TheOpenJournalOfAstrophysics

#astronomy #cosmology #JWST #galaxies #reionization

An article published in the journal "Nature" reports the results of observations of the primordial galaxy JADES-GS-z13-1. A team of researchers used the James Webb Space Telescope to examine this galaxy, estimating that it dates back to about 330 million years after the Big Bang. The surprise came from the so-called Lyman-alpha radiation because it was much stronger than expected from a galaxy of that era.

https://english.tachyonbeam.com/2025/03/27/an-intense-primordial-light-from-the-dark-ages-of-the-universe/

Witnessing the onset of #reionization through Lyman-α emission at redshift 13: https://www.nature.com/articles/s41586-025-08779-5 -> NASA's Webb Sees Galaxy Mysteriously Clearing Fog of Early Universe: https://webbtelescope.org/contents/news-releases/2025/news-2025-116

A #blazar in the epoch of #reionization: https://www.nature.com/articles/s41550-024-02431-4 -> Record discovery points to particle jets, support for rapid #BlackHole formation, in the early universe: https://www.mpia.de/news/science/2024-15-z7-blazar

#Cosmology #Reionization #CMB
"Reionization after JWST: a photon budget crisis?"
🔗https://arxiv.org/abs/2404.07250

"Our current galaxy observations, taken at face value, imply an excess of ionizing photons and thus a process of reionization in tension with the cosmic microwave background and Lyman-α forest."

Another component of the evolution after the Big Bang that is at tension with the Big Bang.

#astronomy #quasar #SMBH #reionization #CosmicDawn

An article published in the journal "The Astrophysical Journal Letters" reports the discovery of the most distant pair of merging quasars known. A team of researchers combined observations from the Subaru Telescope with the Gemini North Telescope to find traces of this pair of quasars that we see as they were about 900 million years after the Big Bang.

Read the details at https://english.tachyonbeam.com/2024/06/20/first-pair-of-merging-quasars-observed-at-cosmic-dawn/

in the #arXiv

The First Billion Years, According to JWST

1.5 years into the JWST science mission, a snapshot of the great progress made towards understanding the initial chapters of our cosmic history.
by Angela Adamo and co-authors
https://arxiv.org/abs/2405.21054

#JWST #EarlyUniverse #Cosmology #galaxies #AGN #reionization #Universe #DarkMatter #astronomy #astrophysics #astrodon #science #STEM

#JWST finds ‘smoking gun’ evidence of early galaxies transforming the #universe

https://physicsworld.com/a/jwst-finds-smoking-gun-evidence-of-early-galaxies-transforming-the-universe/

Distant #quasar sheds light on the #reionization of the #cosmos

#astronomy

Deciphering Lyman-α emission deep into the epoch of #reionization: https://www.nature.com/articles/s41550-023-02179-3 -> Webb reveals that galaxy mergers are the solution to early Universe mystery: https://esawebb.org/news/weic2402/ and https://www.ast.cam.ac.uk/content/webb.reveals.galaxy.mergers.are.solution.early.universe.mystery

Strong (Hb + [OIII]) and Ha emitters at redshift z≃7−8 unveiled with JWST/NIRCam and MIRI imaging in the Hubble eXtreme Deep Field (XDF): https://arxiv.org/abs/2301.10717 -> #MIRI instrument on #JWST detects H-alpha emission during the Epoch of #Reionization for the first time: https://www.astronomie.nl/nieuws/en/miri-instrument-on-jwst-detects-h-alpha-emission-during-the-epoch-of-reionization-for-the-first-time-3785

#astronomy #cosmology #stars #galaxies #reionization #JWST
An article published in the journal "Astronomy & Astrophysics" reports the identification of a group of primordial galaxies that could be among the ones that contributed to the reionization of the universe, making it go from dark to bright. A team of researchers used observations conducted with the James Webb space telescope within the GLASS-JWST program to study 29 very distant and therefore ancient galaxies.

https://english.tachyonbeam.com/2023/03/14/some-of-the-galaxies-that-might-have-turned-the-universe-from-a-dark-place-to-a-bright-one-have-been-identified/

A new supercomputer simulation animates the evolution of the universe

The detailed simulation shows the cosmos changing from a dark, featureless gas to a web of stars and galaxies radiating light.

#cosmology #CreationMyths #UniverseWasAColdDarkPlace #ThenThereWasLight #reionization #spinoza

https://www.sciencenews.org/article/universe-evolution-supercomputer-animation-stars-galaxies