Archive for Astrophysics of Galaxies

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

Posted in OJAp Papers, Open Access, The Universe and Stuff with tags , , , , , , , , , , , , , , , , , , , , , , , , on October 4, 2025 by telescoper

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.

Weekly Update from the Open Journal of Astrophysics – 27/09/2025

Posted in OJAp Papers, Open Access, The Universe and Stuff with tags , , , , , , , , , , , , , , , , , , , , , , on September 27, 2025 by telescoper

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 new papers, which brings the number in Volume 8 (2025) up to 141, and the total so far published by OJAp up to 376.

The first paper to report this week is “The Bispectrum of Intrinsic Alignments: Theory Modelling and Forecasts for Stage IV Galaxy Surveys” by Thomas Bakx (Utrecht U., NL), Alexander Eggemeier (U. Bonn, DE), Toshiki Kurita (MPA Garching, DE), Nora Elisa Chisari (Leiden U., NL) and Zvonimir Vlah (Ruđer Bošković Institute, Croatia). This paper was published on Monday 22nd September 2025 in the folder Cosmology and NonGalactic Astrophysics. It studies the bispectrum of intrinsic galaxy alignments, a possible source of systematic errors in extracting cosmological information from the analysis of weak lensing surveys.

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 Tuesday 23rd September 2025 is “Reanalysis of Stage-III cosmic shear surveys: A comprehensive study of shear diagnostic tests” by Jazmine Jefferson (University of Chicago, USA) and 13 others for the LSST Dark Energy Science Collaboration. It is also in the folder Cosmology and NonGalactic Astrophysics; it describes diagnostic tests on three public shear catalogs (KiDS-1000, Year 3 DES-Y3 s, and Year 3 HSC-Y3); not all the surveys pass all the tests.

The corresponding overlay is here:

You can find the officially accepted version on arXiv here.

The third one this week, published on Wednesday 24th September 2025 in the folder Astrophysics of Galaxies, is “Is feedback-free star formation possible?” by Andrea Ferrara, Daniele Manzoni, and Evangelia Ntormousi (all of the Scuola Normale Superiore, Pisa, Italy). This paper presents an argument that Lyman-alpha radiation pressure strongly limits star formation efficiency, even at solar metallicities, so that a feedback-free star formation phase is not possible without feedback. The overlay is here:

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

Next we have “Microphysical Regulation of Non-Ideal MHD in Weakly-Ionized Systems: Does the Hall Effect Matter?” by Philip F. Hopkins (Caltech, USA), Jonathan Squire (U. Otago, New Zeland), Raphael Skalidis (Caltech) and Nadine H. Soliman (Caltech). This was also published on Wednesday 24th September 2025, but in the folder Earth and Planetary Astrophysics. It presents an improved treatment of non-ideal effects in magnetohydrodynamics, particularly the Hall effect, and a discussion of the implications for weakly-ionized astrophysical systems.

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 is “The Local Volume Database: a library of the observed properties of nearby dwarf galaxies and star clusters” by Andrew B. Pace (University of Virginia, USA). This one was published on Friday 26th September (i.e. yesterday) in the folder Astrophysics of Galaxies. It presents a catalogue of positional, structural, kinematic, chemical, and dynamical parameters for dwarf galaxies and star clusters in the Local Volume. The overlay is here:

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

 

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

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

Posted in OJAp Papers, Open Access, The Universe and Stuff with tags , , , , , , , , , , , , , , , on August 30, 2025 by telescoper

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.

Weekly Update from the Open Journal of Astrophysics – 09/08/2025

Posted in OJAp Papers, Open Access, The Universe and Stuff with tags , , , , , , , , , , , , , , , , , , , , , on August 9, 2025 by telescoper

It’s Saturday morning so, once again, it’s time for an 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 114, and the total so far published by OJAp up to 349.

The 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 “Caught in the Act of Quenching? – A Population of Post-Starburst Ultra-Diffuse Galaxies” by Loraine Sandoval Ascencio & M. C. Cooper (UC Irvine), Dennis Zaritsky, Richard Donnerstein & Donghyeon J. Khim (U. Arizona) and Devontae C. Baxter (UC San Diego). This paper was puvblished on Monday 4th August and is in the folder marked Astrophysics of Galaxies. It discusses a sample of Ultra-Diffuse Galaxies (UDGs) found to be post-starburst galaxies through spectroscopic analysis analysis of candidates selected from the Systematically Measuring Ultra-Diffuse Galaxies (SMUDGes) program.

The overlay is here:

 

 

The officially-accepted version can be found on arXiv here.

Next one up, published on Tuesday 5th August, in the folder Cosmology and Nongalactic Astrophysics, is “Damping Wing-Like Features in the Spectra of High Redshift Quasars: a Challenge for Fully-Coupled Simulations” by Nick Gnedin & Hanjue Zhu (University of Chicago, USA).  This paper presents a discussion of the difficulties that cosmological radiation transfer codes have in accounting for the existence of “neutral islands” in the universe at relatively low redshifts.

The overlay is here:

 

 

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

The third paper of the week is “Spectroscopic Analysis of Pictor II: a very low metallicity ultra-faint dwarf galaxy bound to the Large Magellanic Cloud” by Andrew Pace (U. Virginia, USA) and 32 others based in the USA, UK, Canada, Chile and Spain. This one was also published on Tuesday 5th August but in the folder Astrophysics of Galaxies. It describes Magellan/IMACS and Magellan/MIKE spectroscopy of the ultra-faint dwarf (UFD) galaxy Pictor II, which is located only 12 kpc from the Large Magellanic Cloud (LMC).

The overlay is here:

 

The final version is on arXiv here.

The fourth, and final, paper of the week, also published on Thursday 7th August, is “ASASSN-24fw: An 8-month long, 4.1 mag, optically achromatic and polarized dimming event” by Raquel Forés-Toribio (Ohio State University) and 22 others based in the USA, Austria, Chile and Australia. It is published in the folder Solar and Stellar Astrophysics, and it presents an observational study of an unusual dimming event likely to have been caused by eclipsing of a binary system by a dusty disk.

Here is the overlay:

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

And that’s all the papers for this week. I’ll do another update next Saturday.

P.S. For those of you who missed the post I did earlier in the week, I have been looking at the accounts for the Open Journal of Astrophysics and can confirm that the cost to us per paper is less than $30 and will reduce with scale. We expect to publish around 180 papers in 2025 for which the total cost incurred by OJAp will be around $5000. Obviously if we increase by a factor, say, ten then that amount would become significant so we are taking steps to secure additional funding in the event that happens.

Weekly Update from the Open Journal of Astrophysics – 02/08/2025

Posted in OJAp Papers, Open Access, The Universe and Stuff with tags , , , , , , , , , , , , , , , , , , , , , , , , , , , , on August 2, 2025 by telescoper

It’s Saturday morning again, and it’s the start of a new month, so it’s time for an update of papers published at the Open Journal of Astrophysics. Since the last update we have published five new papers, which brings the number in Volume 8 (2025) up to 110, and the total so far published by OJAp up to 345. I expect we’ll the total number we published last year (120) sometime this month. I predict that by the end of this year we will have published around 180 papers in Volume 8 and around 400 altogether.

The 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 “The matter with(in) CPL” by Leonardo Giani (U. Queensland, Australia), Rodrigo Von Marttens (Universidade Federal da Bahia, Brazil) and Oliver Fabio Piattella (Universita degli Studi dell’Insubria, Italy). This was published on Monday 29th July 2025 in the folder Cosmology and Nongalactic Astrophysics. This article presents a new parameterization of the standard model and its implications for the interpretation of cosmological observations.

The overlay is here:

 

The officially-accepted version can be found on arXiv here.

The second paper of the week, published on Tuesday 30th July in the folder Instrumentation and Methods for Astrophysics, is “An automated method for finding the most distant quasars” by Lena Lenz, Daniel Mortlock, Boris Leistedt & Rhys Barnett (Imperial College London, UK) and Paul C. Hewett (U. Cambridge, UK)”.  This paper presents an automated, reproduceable and objective high-redshift quasar selection pipeline, tested on simulations and real data from the Sloan Digital Sky Survey (SDSS) and UKIRT Infrared Deep Sky Survey (UKIDSS). The overlay is here:

 

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

The third paper of the week is “Early Post Asymptotic Giant Branch Instability: Does it Affect White Dwarf Hydrogen Envelope Mass?” by James MacDonald (University of Delaware, USA). This one was published on Friday 1st Auguest (i.e. yesterday) in the folder Solar and Stellar Astrophysics. It is an investigation into whether Early Post AGB Instability (EPAGBI) can affect determinations of the total abundance of hydrogen in white dwarf stars.

The overlay is here:

The final version is on arXiv here.

 

The fourth paper of the week, also published on Friday 1st August, is “Light Echoes of Time-resolved Flares and Application to Kepler Data” by Austin King and Benjamin C. Bromley (University of Utah, USA).  This describes a new model for circumstellar disks that incorporates echoes produced by extended, time-resolved flares. It is published in the folder Solar and Stellar Astrophysics. Here is the overlay:

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

 

 

The fifth and final article published this week, also published on Friday 1st August,  is “Wide Binaries from Gaia DR3 : testing GR vs MOND with realistic triple modelling” by Charalambos Pittordis, Will Sutherland and Paul Shepherd (Queen Mary, University of London, UK). This presents a test for modified gravity from a sample of wide-binary stars from Gaia DR3, finding that (unmodified) Newtonian gravity provides a better fit to the data. It is in the folder Astrophysics of Galaxies.

The overlay is here:

 

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

And that’s all the papers for this week. I’ll do another update next Saturday.

Weekly Update from the Open Journal of Astrophysics – 26/07/2025

Posted in OJAp Papers, Open Access, The Universe and Stuff with tags , , , , , , , , , , , , , , , , , , , , , on July 26, 2025 by telescoper

It’s Saturday morning again, so it’s time again for an update of papers published at the Open Journal of Astrophysics. Since the last update we have published seven new papers, which brings the number in Volume 8 (2025) up to 105, and the total so far published by OJAp up to 340. I expect we’ll pass the century for this year sometime next week. I had expected a bit of a slowdown in July, but that doesn’t seem to have happened. Anyway, with the century for the year having been achieved, the next target is 120 (the total number we published last year). At the current rate I expect us to reach that sometime in August.

The 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 “Non-equilibrium ionization in the multiphase circumgalactic medium – impact on quasar absorption-line analyses” by Suyash Kumar and Hsiao-Wen Chen (University of Chicago, USA). This was published on Tuesday 22nd July 2025 in the folder Astrophysics of Galaxies. It discusses time-dependent photoionization (TDP) models that self-consistently solve for the ionization state of rapidly cooling gas irradiated by the extragalactic ultraviolet background (UVB) and the application thereof to observed systems.

The overlay is here:

The officially-accepted version can be found on arXiv here.

The second paper of the week, also published on Tuesday 22nd July but in the folder Cosmology and Nongalactic Astrophysics, is “Do We Know How to Model Reionization?” by Nick Gnedin (University of Chicago, USA). This paper discusses the similarities and differences between the radiation fields produced by different numerical simulations of cosmic reionization. The overlay is here:

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

The third paper of the week is “The effects of projection on measuring the splashback feature” by Xiaoqing Sun (MIT), Stephanie O’Neil (U. Penn.), Xuejian Shen (MIT) and Mark Vogelsberger (MIT), all based in the USA. This paper describes an investigation whether projection effects could lead to any systematic bias in determining the position of the boundary between infalling and accreting matter around haloes. It was published on Wednesday 23rd July in the folder Astrophysics of Galaxies. The overlay is here:

The officially-accepted version can be found on arXiv here.

The fourth paper of the week, also published on Wednesday 22nd July in the folder Astrophysics of Galaxies, is “Host galaxy identification of LOFAR sources in the Euclid Deep Field North” by Laura Bisigello, Marika Giulietti, Isabella Prandoni, Marco Bondi, & Matteo Bonato (INAF, Bologna, Italy), Manuela Magliocchetti (INAF-IAPS Roma, Italy), Huub Rottgering (Leiden Observatory, Netherlands), Leah, K. Morabito (Durham University, UK) and Glenn, J. White (Open Universirty, UK). This presents a catalogue of optical and near-infrared counterparts to radio sources detected in the Euclid Deep Field North using observations from the LOw-Frequency ARray (LOFAR). The overlay is here:

The final, accepted version of the paper is on arXiv here.

Fifth one up is “Constraining the dispersion measure redshift relation with simulation-based inference” by Koustav Konar (Ruhr University Bochum), Robert Reischke (Universität Bonn), Steffen Hagstotz (Ludwig-Maximilians Universität München), Andrina Nicola (Bonn) and Hendrik Hildebrandt (Bochum); all authors based in Germany. This was published on Thursday 24th July in the folder Cosmology and NonGalactic Astrophysics. It discusses using simulations to develop the use of Dispersion Measures of Fast Radio Bursts as cosmological probes. The overlay is here:

You can find the officially accepted version on arXiv here.

The penultimate (sixth) article published this week is “Generating Dark Matter Subhalo Populations Using Normalizing Flows” by Jack Lonergan (University of Southern California), Andrew Benson (Carnegie Observatories) and Daniel Gilman (University of Chicago), all based in the USA. This paper describes a generative AI approach to subhalo populations, trained using the semi-analytical model Galacticus. This paper was published yesterday (i.e. on Friday 25th July) in the folder Astrophysics of Galaxies.

You can find the final version on arXiv here.

The last article published this week is “21 Balmer Jump Street: The Nebular Continuum at High Redshift and Implications for the Bright Galaxy Problem, UV Continuum Slopes, and Early Stellar Populations” by Harley Katz of the University of Chicago, and 13 others based in the USA, UK, Germany, Denmark and Austria. This discusses the implications of extreme nebular emission for the spectroscopic properties of galaxies, especially at high redshift. It was published on Friday 25th July in the folder Astrophysics of Galaxies.

The overlay is here:

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

And that’s all the papers for this week. I’ll do another update next Saturday, when we’ll be into August.

Weekly Update from the Open Journal of Astrophysics – 12/07/2025

Posted in OJAp Papers, Open Access, The Universe and Stuff with tags , , , , , , , , , , , , , , , , , , , , , , , , , on July 12, 2025 by telescoper

It’s Saturday morning again, so it’s time again for an update of papers published at the Open Journal of Astrophysics. Since the last update we have published seven new papers, which brings the number in Volume 8 (2025) up to 92, and the total so far published by OJAp  up to 327.

This was a slightly strange week, starting with the fact that there were no new arXiv announcements on Monday 7th July because of the 4th July holiday in the USA on Friday so no papers were published that day. We were not able to publish any papers on Wednesday 9th July either because Crossref was offline for 24 hours that day while its data was migrated into the cloud. Our publishing process requires a live connection with Crossref to deposit metadata upon publication so we can’t publish while that service is down. Fortunately the update seems to have gone well and normal services resumed the following day. That partially accounts for the fact that four of this week’s papers were published on 10th July.

Anyway, The 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 “The Jackknife method as a new approach to validate strong lens mass models” by Shun Nishida & Masamune Oguri (Chiba University, Japan) , Yoshinobu Fudamoto (Steward Observatory, USA) and Ayari Kitamura (Tohoku University, Japan). This article, which is in the folder marked Cosmology and NonGalactic Astrophysics,  describes and application of the Jackknife statistical resampling techique to gravitational lensing by removing lensed images and recalcualting the mass modelIt was published on Tuesday 8th July 2025. The overlay is here:

 

The officially-accepted version can be found on arXiv here.

The second paper is “Low redshift post-starburst galaxies host abundant HI reservoirs” by Sara Ellison (U. Victoria, Canada) and 10 others based in China, UK, Spain, USA and Canada.  This one was also published oon Tuesday 8th July but in the folder Astrophysics of Galaxies. This paper uses 21cm observations of a sample of post-starburst galaxies, to show  that they contain large reservoirs of neutral hydrogen. Here is the overlay:

You can find the final version of the manuscript on arXiv here.

Next one up, one of four published on Thursday 10th July, is “Predicting the number density of heavy seed massive black holes due to an intense Lyman-Werner field” by Hannah O’Brennan (Maynooth University, Ireland) and 7 others based in Ireland, USA and Italy. This paper presents an exploration of the scenario for black hole formation driven by Lyman-Werner photons (i.e. ultraviolet radiation in the range 11.2 to 13.6 eV). It is in the folder marked Cosmology and NonGalactic Astrophysics, and the overlay is here:

 

You can read the final accepted version on arXiv here.

The fourth paper this week, and the second published on 10th July, is “Chemical Abundances in the Metal-Poor Globular Cluster ESO 280-SC06: A Formerly Massive, Tidally Disrupted Globular Cluster” by Sam A. Usman (U. Chicago, USA) and 8 others based in the USA, Canada and Australia. This paper, which is in the folder Astrophysics of Galaxies, presents a detailed spectroscopic study of the chemical abundances in a Milky Way globular cluster ESO 280-SC06. The overlay is here:

The officially accepted version of the paper can be read here.

Next one up, also published on 10th July and also in the folder marked Astrophysics of Galaxies is “Predictions for the Detectability of Milky Way Satellite Galaxies and Outer-Halo Star Clusters with the Vera C. Rubin Observatory” by Kabelo Tsiane (U. Michigan) and 9 others on behalf of the LSST Dark Energy Science Collaboration.

The overlay is here:

 

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

The penultimate paper for this week, and the last of the batch published on 10th July,  is “Systematically Measuring Ultra-Diffuse Galaxies. VIII. Misfits, Miscasts, and Miscreants” by Dennis Zaritsky, Richard Donnerstein, and Donghyeon J. Khim (Steward Observatory, U. Arizona, USA). This paper presents a morphological study of weird and wonderful galaxies as part of an effort to Systematically Measure Ultra-Diffuse Galaxies (the SMUDGes survey). It is in the folder marked Astrophysics of Galaxies. The overlay is here:

 

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

The last article published this week is “Differential virial analysis: a new technique to determine the dynamical state of molecular clouds” by Mark R. Krumholz (ANU, Australia), Charles J. Lada (Harvard, USA) & Jan Forbrich (U. Herts, UK). This paper presents simple analytic models of supported and collapsing molecular clouds, tested using full 3D simulations and applied to observed clouds in Andromeda. It is in the folder marked Astrophysics of Galaxies and was published yesterday, i.e on Friday 11th July 2025. Here is the overlay

 

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

And that’s all the papers for this week. I will, however, take this opportunity to mention that a while ago I was interviewed about the Open Journal of Astrophysics by Colin Stuart on behalf of the Foundational Questions Institute; the write-up of the interview can be found here.

Weekly Update from the Open Journal of Astrophysics: 05/07/2025

Posted in OJAp Papers, Open Access, The Universe and Stuff with tags , , , , , , , , , , , , , , , , , on July 5, 2025 by telescoper

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 three new papers, which brings the number in Volume 8 (2025) up to 85, and the total so far published by OJAp  up to 320.

The three 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 “Stellar reddening map from DESI imaging and spectroscopy” by Rongpu Zhou (Lawrence Berkeley National Laboratory, USA) and an international case of 56 others too numerous to mention individually. This paper was published on 1st July 2025 in the folder marked Astrophysics of Galaxies. It describes maps of stellar reddening by Galactic dust inferred from observations obtained using the Dark Energy Spectroscopic Instrument, and a comparison with previous such maps. The overlay is here:

You can find the final, accepted, version on arXiv here.

Next one up is “On inertial forces (indirect terms) in problems with a central body” by Aurélien Crida (Université Côte d’Azur, France) and 17 others – again too numerous to be listed individually – based in France, Italy, Germany, Mexico and the USA. This paper discusses the indirect terms that arise the Newtonian dynamics of multi-body systems dominated by a central massive body, upon which other bodies exert a gravitational pull, when the massive body is treated as the origin of the coordinate system. This one, also published on July 1st 2025, is in the folder marked Earth and Planetary Astrophysics.

The overlay is here:

You can find the officially accepted version on arXiv here.

The last paper of this batch is “Stellar ejection velocities from the binary supernova scenario: A comparison across population synthesis codes” by Tom Wagg (U. Washington, USA), David D. Hendriks (U. Surrey, UK), Mathieu Renzo (U. Arizona, USA) and Katelyn Breivik (Carnegie Mellon U., USA). It was published on July 2nd 2025 in the folder Solar and Stellar Astrophysics and it presents comparison of the ejection velocities of stars ejected from binary systems by supernova explosions predicted in three different population synthesis codes.

The overlay is here:

You can read the final accepted version on arXiv here.

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

Weekly Update from the Open Journal of Astrophysics – 28/06/2025

Posted in OJAp Papers, Open Access, The Universe and Stuff with tags , , , , , , , , , , , , , , , , , , , , , , , , on June 28, 2025 by telescoper

It’s Saturday morning again so time for an update of papers published at the Open Journal of Astrophysics. Since the last update we have published eight new papers, which brings the number in Volume 8 (2025) up to 82, and the total so far published by OJAp  up to 317. With about half the year gone, we’re on target to published around 160 papers this year.

The 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 “Spectroscopic and X-ray Modeling of the Strong Lensing Galaxy Cluster MACS J0138.0-2155” by Abigail Flowers (University of California at Santa Cruz; UCSZ), Jackson H. O’Donnell (UCSZ), Tesla E. Jeltema (UCSZ), Vernon Wetzell (U. Pennsylvania) & M. Grant Roberts (UCSZ). This artticle, which is in the folder marked Cosmology and NonGalactic Astrophysics, presents a study of the mass distribution and substructure of a galaxy cluster that acts as a gravitational lens for a source galaxy at z=1.95 that contains two supernovae. It was published on 23rd June 2025. The overlay is here:

The officially-accepted version can be found on arXiv here.

Illuminating the Physics of Dark Energy with the Discovery Simulations” by Gillian D. Beltz-Mohrmann (Argonne National Laboratory, USA) and 12 others based in the USA and Spain. This describes new high-resolution cosmological simulations providing a testbed for alternative cosmological probes that may offer additional constraining power beyond Baryon Accoustic Oscillations. It is filed in the folder marked Cosmology and NonGalactic Astrophysics.

The overlay is here:

You can read the final accepted version on arXiv here.

Next one up is in the folder marked Astrophysics of Galaxies. The title is “On the minimum number of radiation field parameters to specify gas cooling and heating functions” and it is by David Robinson & Camille Avestruz (U. Michigan) and Nickolay Y. Gnedin (U.Chicago) and was published on 23rd June 2025. It presents an analysis using machine learning of atomic gas cooling and heating functions computed by the spectral synthesis code Cloudy.

The overlay is here:

 

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

The thirtd paper is “On the Use of WGANs for Super Resolution in Dark-Matter Simulations” by John Brennan (Maynooth), Sreedhar Balu (U. Melbourne), Yuxiang Qin (ANU), John Regan (Maynooth) and Chris Power (U. Western Australia). This one is also in the folder marked Astrophysics of Galaxies and was also published on Monday 23rd June. It is about using the Wasserstein Generative Adversarial Network (WGAN) model to increase the particle resolution of dark-matter-only simulations of galaxy formation. The overlay is here:

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

Next we have “Cosmic Rays Masquerading as Hot CGM Gas: An Inverse-Compton Origin for Diffuse X-ray Emission in the Circumgalactic Medium” by Philip F. Hopkins (Caltech), Eliot Quataert (Princeton), Sam B. Ponnada (Caltech) and Emily Silich (Caltech), all based in the USA.  This one was published on 24th June 2025 in the folder High-Energy Astrophysical Phenomena

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

The fifth paper this week is “Compact Binary Formation in Open Star Clusters III: Probability of Binary Black Holes Hidden Inside of Gaia Black Hole Binary” by Ataru Tanikawa (Fukui Prefectural University, Japan), Long Wang (Sun Yat-sen University, China), Michiko S. Fujii (University of Tokyo, Japan), Alessandro A. Trani (Niels Bohr Institute, Denmark), Toshinori Hayashi (Kyoto University, Japan) and Yasushi Suto (Kochi University of Technology, Japan).  This one is in the folder marked Astrophysics of Galaxies and was published on Tuesday 24th June. It presents an investigation into whether some Gaia black hole binary systems may in fact involve three black holes, including a pair too compact to be resolved astrometrically. Here is the overlay:

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

Next we have “Rapid identification of lensed type Ia supernovae with color-magnitude selection” by Prajakta Mane (IISER) and Anupreeta More & Surhud More (IUCAA), all based in India. This paper presents an  extension of the use of color-magnitude diagrams, used previously as a means to identify lensed supernovae, with applications to LSST-like photometric data. It is in the folder marked Astrophysics of Galaxies and was published on Thursday 26th June.

The officially-accepted version of the article can be found on arXiv here.

The penultimate article this week is: “Cosmic Reionization On Computers: Biases and Uncertainties in the Measured Mean Free Path at the End Stage of Reionization” by Huanqing Chen (U. Alberta, Canada), and Jiawen Fan & Camille Avestruz (U. Michigan, USA). This one is in the folder Cosmology and Nongalactic Astrophysics and was published on 26th June 2025.  This paper studies possible systematic effects in computer simulations of cosmic reionization especially when it results from quasar radiation.

The overlay is here:

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

Eighth and last paper this week is “Exploring the Core-galaxy Connection” by Isabele Lais de Souza Vitório (U. Michigan) and Michael Buehlmann, Eve Kovacs, Patricia Larsen, Nicholas Frontiere & Katrin Heitmann (Argonne National Laboratory, USA).  This one is in the folder Cosmology and Nongalactic Astrophysics and was published on Friday 27th June 2025 (i.e. yesterday).

The overlay is here:

 

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

And that’s all the papers for this week. I do, however, have some more news to pass on. We are delighted to welcome two new recruits to our Editorial Board,  Dr Foteini Oikonomou of the Norwegian University of Science and Technology, who specializes in the application of particle physics theories to  high-energy astrophysical phenomena, and Dr Heloise Stevance of Oxford University (UK), who specializes in the interface between Machine Learning and Astrophysics.

Weekly Update from the Open Journal of Astrophysics – 20/06/2025

Posted in OJAp Papers, Open Access, The Universe and Stuff with tags , , , , , , , , , , , , , , , on June 20, 2025 by telescoper

Yesterday (Thursday 19th June 2025) was a national holiday in the USA, which means that no new papers were announced on arXiv today (Friday 20th June). I have therefore decided to bring forwarded the usual weekly update of papers published at the Open Journal of Astrophysics by a day. Since the last update we have published three new papers, which brings the number in Volume 8 (2025) up to 74, and the total so far published by OJAp  is now up to 309.

The three papers published this week, with their overlays, are as follows. All three were published on Tuesday, June 17th 2025. 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 “Illuminating the Physics of Dark Energy with the Discovery Simulations” by Gillian D. Beltz-Mohrmann (Argonne National Laboratory, USA) and 12 others based in the USA and Spain. This describes new high-resolution cosmological simulations providing a testbed for alternative cosmological probes that may offer additional constraining power beyond Baryon Accoustic Oscillations. It is filed in the folder marked Cosmology and NonGalactic Astrophysics.

The overlay is here:

You can read the final accepted version on arXiv here.

The second paper is in the folder marked Astrophysics of Galaxies. It is “LIGHTS. The extended point spread functions of the LIGHTS survey at the LBT” by Nafise Sedighi (Instituto de Astrofísica de Canarias, Spain) and 15 others based in Spain, USA, Iran, Italy and the UK. It describes the procedure used to construct the extended Point Spread Functions (PSFs) of the LIGHTS survey in images taken with the Large Binocular Cameras (LBCs) of the Large Binocular Telescope (LBT).

The overlay is here:

 

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

Finally this week we have “Fast radio bursts as a probe of gravity on cosmological scales” by Dennis Neumann (Leiden University, Netherlands), Robert Reischke (Universität Bonn, Germany), Steffen Hagstotz (Ludwig-Maximilians Universität München, Germany) and Hendrik Hildebrandt (Ruhr University Bochum, Germany). This is about using dispersion measures derived from Fast Radio Bursts (FRBs) in combination with cosmic shear to investigate modified gravity theories, specifically Horndeski gravity. It is in the folder marked Cosmology and NonGalactic Astrophysics.

The overlay is here:

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

That’s all the papers for this week. I’ll revert to the usual schedule for updates next week, and post the next one on Saturday 28th June.