Archive for Astrid Simulations

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

Posted in OJAp Papers, Open Access, The Universe and Stuff with tags , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , on February 7, 2026 by telescoper

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:

Open Journal of Astrophysics

New Publication at the Open Journal of Astrophysics: "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)

doi.org/10.33232/001c.156097

February 2, 2026, 11:02 am 1 boosts 1 favorites

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:

Open Journal of Astrophysics

New Publication at the Open Journal of Astrophysics: "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

doi.org/10.33232/001c.156099

February 2, 2026, 11:23 am 1 boosts 0 favorites

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:

Open Journal of Astrophysics

New Publication at the Open Journal of Astrophysics: "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)

doi.org/10.33232/001c.156223

February 4, 2026, 8:20 am 1 boosts 0 favorites

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:

Open Journal of Astrophysics

New Publication at the Open Journal of Astrophysics: "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)

doi.org/10.33232/001c.156224

February 4, 2026, 8:40 am 1 boosts 0 favorites

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:

Open Journal of Astrophysics

New Publication at the Open Journal of Astrophysics: "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)

doi.org/10.33232/001c.156271

February 5, 2026, 7:39 am 1 boosts 1 favorites

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:

Open Journal of Astrophysics

New Publication at the Open Journal of Astrophysics: "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)

doi.org/10.33232/001c.156361

February 6, 2026, 7:43 am 1 boosts 0 favorites

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

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

Posted in OJAp Papers, Open Access, The Universe and Stuff with tags , , , , , , , , , , , , , , , , , , , , , , , , , , , on January 31, 2026 by telescoper

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 four 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:

Open Journal of Astrophysics

New Publication at the Open Journal of Astrophysics: "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.

doi.org/10.33232/001c.155802

January 26, 2026, 11:46 am 0 boosts 1 favorites

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:

Open Journal of Astrophysics

New Publication at the Open Journal of Astrophysics: "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)

doi.org/10.33232/001c.155822

January 27, 2026, 8:49 am 1 boosts 0 favorites

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:

Open Journal of Astrophysics

New Publication at the Open Journal of Astrophysics: "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

doi.org/10.33232/001c.155863

January 27, 2026, 9:55 am 1 boosts 0 favorites

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:

Open Journal of Astrophysics

New Publication at the Open Journal of Astrophysics: "A Cosmic Miracle: A Remarkably Luminous Galaxy at $z_{rm spec} = 14.44$ Confirmed with JWST" by Rohan Naidu (MIT Kavli Institute) and 45 others.

doi.org/10.33232/001c.156033

January 30, 2026, 7:20 am 2 boosts 1 favorites

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

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

Posted in OJAp Papers, Open Access, The Universe and Stuff with tags , , , , , , , , , , , , , , , , , on January 24, 2026 by telescoper

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:

Open Journal of Astrophysics

New Publication at the Open Journal of Astrophysics; "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

doi.org/10.33232/001c.155493

January 19, 2026, 10:33 am 2 boosts 1 favorites

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:

Open Journal of Astrophysics

New Publication at the Open Journal of Astrophysics: "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)

doi.org/10.33232/001c.155624

January 21, 2026, 9:30 am 1 boosts 0 favorites

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:

Open Journal of Astrophysics

New Publication at the Open Journal of Astrophysics: "The Kinematic Properties of TŻO Candidate HV 11417 with Gaia DR3" by Anna J. G. O'Grady (Carnegie Mellon University, USA)

doi.org/10.33232/001c.155625

January 21, 2026, 9:45 am 1 boosts 1 favorites

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