Archive for white dwarfs

Weekly Update from the Open Journal of Astrophysics – 28/02/2026

Posted in OJAp Papers, Open Access, The Universe and Stuff with tags , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , on February 28, 2026 by telescoper

It’s Saturday once more, so it’s time for another update of activity at the Open Journal of Astrophysics. It has been a busy week. Since the last update we have published a further nine papers, bringing the number in Volume 9 (2026) to 45 and the total so far published by OJAp up to 493.

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 four papers this week were all published on Monday 23rd February.

The first paper to report is “A Bayesian Exploration of The Mass of the Ursa Major III: Kinematics, Rotation and their influence on the Mass to Light Ratio” by Tim R. Adams (U. Sydney, Australia), Brendon J. Brewer (U. Auckland, New Zealand) and Geraint F. Lewis (Sydney). This paper, in the folder Astrophysics of Galaxies, describes an investigation of the kinematics of potential ultra-faint dwarf galaxy UMa III/U1, finding a preference for a non-rotating model; the object’s nature remains uncertain.

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: "A Bayesian Exploration of The Mass of the Ursa Major III: Kinematics, Rotation and their influence on the Mass to Light Ratio" by Tim R. Adams (U. Sydney, Australia), Brendon J. Brewer (U. Auckland, New Zealand) and Geraint F. Lewis (Sydney)

doi.org/10.33232/001c.158197

February 23, 2026, 7:35 am 2 boosts 1 favorites

The second paper is “The Impact of Baryonic Effects on the Dynamical Masses Inferred Using Satellite Kinematics” by Josephine F.W. Baggen, Frank C. van den Bosch, and Kaustav Mitra (Yale U., USA). This paper, also in the folder Astrophysics of Galaxies, presents a model to assess the impact of stars and gas on satellite kinematics, showing that these baryonic effects can reduce the satellite velocity dispersion and increase inferred central galaxy masses.

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: "The Impact of Baryonic Effects on the Dynamical Masses Inferred Using Satellite Kinematics" by Josephine F.W. Baggen, Frank C. van den Bosch, and Kaustav Mitra (Yale U., USA)

doi.org/10.33232/001c.158198

February 23, 2026, 7:47 am 1 boosts 1 favorites

The third paper this week, and the third published on Monday 23rd February, and the third in the folder Astrophysics of Galaxies, is “MEGATRON: Disentangling Physical Processes and Observational Bias in the Multi-Phase ISM of High-Redshift Galaxies” by Nicholas Choustikov (U. Oxford, UK) and 12 others based in UK, USA, France, Korea and Belgium. The study uses MEGATRON simulations to analyze the interstellar medium (ISM) of high-redshift galaxies, finding it denser and less metal-enriched than local galaxies with implications for line ratios as diagnostics

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: "MEGATRON: Disentangling Physical Processes and Observational Bias in the Multi-Phase ISM of High-Redshift Galaxies" by Nicholas Choustikov (U. Oxford, UK) and 12 others based in UK, USA, France, Korea and Belgium

doi.org/10.33232/001c.158199

February 23, 2026, 8:02 am 2 boosts 1 favorites

The fourth paper this week, also published on Monday 23rd February, but in the folder Instrumentation and Methods for Astrophysics, is “Redshift Assessment Infrastructure Layers (RAIL): Rubin-era photometric redshift stress-testing and at-scale production” by the RAIL Team (31 authors) and the Dark Energy Science Collaboration. The article introduces Redshift Assessment Infrastructure Layers (RAIL), an open-source Python library for large-scale probabilistic photo-z estimation, useful for extragalactic research and not limited to LSST data.

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: "Redshift Assessment Infrastructure Layers (RAIL): Rubin-era photometric redshift stress-testing and at-scale production" by the RAIL Team (31 authors) and the Dark Energy Science Collaboration

doi.org/10.33232/001c.158200

February 23, 2026, 8:32 am 1 boosts 1 favorites

Moving on to Tuesday 24th February, the fifth paper this week, is “Feedback shaped the galaxy morphological sequence in presence of mergers” by Masafumi Noguchi (Tohoku University, Japan). This article was published in the folder Astrophysics of Galaxies. This study suggests that galaxy morphology, specifically the mass ratios of bulges and disks, is influenced by galaxy mergers and feedback processes from active galactic nuclei and supernovae.

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: "Feedback shaped the galaxy morphological sequence in presence of mergers" by Masafumi Noguchi (Tohoku University, Japan)

doi.org/10.33232/001c.158272

February 24, 2026, 7:21 am 1 boosts 0 favorites

The sixth paper this week is “HelioSpectrotron 5000: an interactive solar atlas” by Alexander G.M. Pietrow (AIP Potsdam, Germany). This was published on Tuesday 24th February in the folder Solar and Stellar Astrophysics. This describes HelioSpectrotron~5000 (HS5000), which is an interactive solar spectral atlas that allows comparison between high-resolution spectra and ground-based instrument observations, aiding in wavelength calibration and line identification. The software can be found here; I had a play with it yesterday and it’s very easy to use!

The overlay is here:

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

Open Journal of Astrophysics

New Publication at the Open Journal of Astrophysics: "HelioSpectrotron 5000: an interactive solar atlas" by Alexander G.M. Pietrow (AIP Potsdam, Germany)

doi.org/10.33232/001c.158273

February 24, 2026, 7:35 am 1 boosts 0 favorites

The seventh paper of this week was published on Thursday 26th February is “The Rise of Ionized Gas Filaments in Early-Type Galaxies” by Ryan Eskenasy (U. Kentucky, USA), Valeria Olivares (Universidad de Santiago de Chile) and Yuanyuan Su (U. Kentucky, USA). This article, in the folder Astrophysics of Galaxies, is an exploration of the formation of multiphase filamentary nebulae in early-type galaxies (ETGs), using VLT-MUSE IFU observations of 126 non-central ETGs, focussing on the hot gas components thereof.

The overlay is here:

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

Open Journal of Astrophysics

New Publication at the Open Journal of Astrophysics: "The Rise of Ionized Gas Filaments in Early-Type Galaxies" by Ryan Eskenasy (U. Kentucky, USA), Valeria Olivares (Universidad de Santiago de Chile) and Yuanyuan Su (U. Kentucky, USA)

doi.org/10.33232/001c.158379

February 26, 2026, 7:27 am 1 boosts 0 favorites

Number eight for this week is “Relationship Between Major Stellar Physical Parameters and Normal Mode Frequencies in Accreting White Dwarf Stars” by Praphull Kumar, Dean M. Townsley and Hunter Anz (U. Alabama, USA). This was published on Thursday 26th February in the category Solar and Stellar Astrophysics; the paper presents a new method for identifying pulsation modes in white dwarfs, improving upon previous models by using more realistic parameters and considering thermohaline mixing and element diffusion. The overlay is here:

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

Open Journal of Astrophysics

New Publication at the Open Journal of Astrophysics: "Relationship Between Major Stellar Physical Parameters and Normal Mode Frequencies in Accreting White Dwarf Stars" by Praphull Kumar, Dean M. Townsley and Hunter Anz (U. Alabama, USA)

doi.org/10.33232/001c.158380

February 26, 2026, 7:37 am 1 boosts 0 favorites

The ninth, and final, paper for this week is “A Semi-Supervised Learning Method for the Identification of Bad Exposures in Large Imaging Surveys” by Yufeng Luo (U. Wyoming, USA) and 8 others from the DESI Legacy Imaging Surveys Team. This was published on Friday 27th February, i.e yesterday, in the folder Instrumentation and Methods for Astrophysics. The paper describes a machine-learning approach for detecting poor-quality exposures in large astronomical imaging surveys, proving efficient and accurate in identifying problematic exposures.

The overlay is here:

The official version on arXiv can be found here and the Mastodon announcement follows:

Open Journal of Astrophysics

New Publication at the Open Journal of Astrophysics: "A Semi-Supervised Learning Method for the Identification of Bad Exposures in Large Imaging Surveys" by Yufeng Luo (U. Wyoming, USA) and 8 others from the DESI Legacy Imaging Surveys Team

doi.org/10.33232/001c.158430

February 27, 2026, 8:52 am 1 boosts 1 favorites

And that concludes this week’s update. We have now published 45 papers in two complete months of 2026, on which basis we can estimate about 270 papers in the year. For the record, in the first two months of 2025 we published 21 papers.

P.S. Thank you to the many people who responded to the latest call for editors. I’ve been sending out invitations and getting people onboard as quickly as I can, but I still have a number to get to so please bear with me!

Weekly Update from the Open Journal of Astrophysics – 23/08/2025

Posted in OJAp Papers, Open Access, The Universe and Stuff with tags , , , , , , , , , , , , , , , , , , , , , , , , , on August 23, 2025 by telescoper

So it’s Saturday again, so it’s time 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 six new papers, which brings the number in Volume 8 (2025) up to 122, and the total so far published by OJAp up to 357. As I mentioned here we have overtaken the total of 120 published in Volume 7 (2024) and are on track for in excess of 180 publications in 2025.

The first paper to report this week is “Mass-feeding of jet-launching white dwarfs in grazing and common envelope evolution” by Noam Soker (Technion, Haifa, Israel). This was published on Tuesday 19th August in the folder Solar and Stellar Astrophysics. It proposes a theoretical suggestion about the production of jets in common-envelope evolution with massive stars.

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, published on Wednesday 20th August in the folder Earth and Planetary Astrophysics, is “Transition metal abundance as a key parameter for the search of Life in the Universe” by Giovanni Covone and Donato Giovannelli (University of Naples, Italy). This paper presents an argument that the availability of transition elements is an essential feature of habitability, and should be considered as such in selecting exoplanetary targets in the search for life.

The overlay is here:

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

The third paper this week, also published on 20th August 2025 in the folder Earth and Planetary Astrophysics, is “Discrete element simulations of self-gravitating rubble pile collisions: the effects of non-uniform particle size and rotation” by Job Guidos, Lucas Kolanz and Davide Lazzati (Oregon State University, USA).  This presents a new computer code for simulating the growth of granular masses through collisions of smaller particles and discusses results generated by it.

The overlay for this one is here:

You can find the officially accepted version on arXiv here.

The next paper, the fourth this week, is “Seeing the Outer Edge of the Infant Type Ia Supernova 2024epr in the Optical and Near Infrared” by W.B. Hoogendam (University of Hawaii, USA) and 32 others – too numerous to list by name – based in various institutes in the USA, Australia, UK, Denmark, Taiwan and China. This paper was also published on Wednesday 20th August 2025, but in the folder High-Energy Astrophysical Phenomena.  The article reports on the results of optical-to-near-infrared photometry and spectroscopy of the Type Ia supernova (SN Ia) 2024epr and a discusses how these challenge models for this sort of supernova.

The overlay is here:

You can find the officially accepted version on arXiv here.

The fifth paper this week is “Computing Nonlinear Power Spectra Across Dynamical Dark Energy Model Space with Neural ODEs” by Peter L. Taylor of Ohio State University (USA).  This one shows how to compute the evolution of cosmological power spectra into the non-linear regime via neural differential equations. It was published on Friday 22nd August 2025 in the folder Cosmology and NonGalactic Astrophysics. The overlay is here:

You can find the officially accepted version on arXiv here.

And finally for this week we have “Symbiotic star candidates in Gaia Data Release 3” by Samantha E. Ball & Benjamin C Bromley (University of Utah, USA) and Scott J. Kenyon (Smithsonian Observatory, USA). This paper was published on Friday 22nd August in the folder Solar and Stellar Astrophysics. It describes a new search for symbiotic star candidates in Gaia Data Release 3 (GDR3), based on astrometric, photometric, and spectroscopic information. 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. I suppose there will come a time when we publish a paper on every day of the week and each week’s summary will contain a paper in each of the astro-ph categories on arXiv, but we haven’t done that yet. This week we published on every day but Monday 18th August, and have papers in four of the six categories.

Weekly Update from the Open Journal of Astrophysics – 24/05/205

Posted in OJAp Papers, Open Access, The Universe and Stuff with tags , , , , , , , , , , , , , , , , , on May 24, 2025 by telescoper

It’s  time once again for the regular Saturday update of papers published during the past week 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 62 and the total so far published by OJAp up to 297.

In chronological order of publication, 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: “Jet-shaped filamentary ejecta in common envelope evolution” by Ron Schreier, Shlomi Hillel and Noam Soker (Technion, Haifa, Israel). This paper, which was published on Monday May 19th 2025 in the folder High-Energy Astrophysical Processes, presents three-dimensional hydrodynamical simulations of common envelope evolution of a neutron star inside the envelope of a rotating red supergiant with Rayleigh-Taylor instabilities forming filamentary ejecta.

The overlay is here:

You can find the officially accepted version on arXiv here.

Second one up is “Weighing The Options: The Unseen Companion in LAMOST J2354 is Likely a Massive White Dwarf” by M. A. Tucker, A. J. Wheeler & D. M. Rowan (Ohio State University, USA) and M. E. Huber (U. Hawaii, USA). This paper was published on Tuesday 20th May 2025 in the folder for Solar and Stellar Astrophysics. It discusses a spectroscopic study of the binary system LAMOST J235456.73+335625 (J2354) with a discussion of the implications for the nature of the dark component.

The overlay is here:

 

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

The third and last paper of the week, published on Thursday May 22nd 2025, also in the folder Solar and Stellar Astrophysics, is “How to use Gaia parallaxes for stars with poor astrometric fits” by Kareem El-Badry (Caltech, USA).  This paper presents a method for extracting reasonable estimates of stellar parallaxes from Gaia data when the overall astrometric solution is unreliable due to errors and noise

Here is the overlay:

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

That’s all the papers for this week. Looking at the publishing workflow, I expect we will pass the 300 mark next week. We’ll see when I post the next update next Saturday.

 

Three New Publications at the Open Journal of Astrophysics

Posted in OJAp Papers, Open Access, The Universe and Stuff with tags , , , , , , , , , on January 27, 2024 by telescoper

Once again it’s a good time for a roundup of the week’s business at the  Open Journal of Astrophysics. This past week we have once again published three papers, taking  the count in Volume 7 (2024) up to 7 and the total published by OJAp up to 122. Looking at the current work flow I expect there to be at least three next week too.

In chronological order, 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.

First one up is “The extraordinary frequency pattern variation in δ Scuti stars” by  Luis A. Balona of the South African Astronomical Observatory in Cape Town, South Africa. This paper, published on 22nd  January 2024, is a study of the (lack of) correlation in the structure of periodograms in Transiting Exoplanet Survey Satellite (TESS) data relating to a oscillating delta Scuti variable stars. This paper is in the category of Solar and Stelllar Astrophysics.

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

 

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

The second paper to announce is “The Millions of Optical-Radio/X-ray Associations (MORX) Catalogue, v2” by Eric Wim Flesch, an independent researcher based in New Zealand.  This presents the MORX catalogue of optical/radio/X-ray/ galaxy associations, containing over three million objects. The catalogue itself can be found in a number of locations on the web, e.g. here or here.

The paper was also published on 23rdJanuary 2024 in the category Astrophysics of Galaxies . You can see the overlay here:

 

 

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

The last paper of this batch is  entitled “The runaway velocity of the white dwarf companion in the double detonation scenario of supernovae” and the authors are Jessica Braudo and Noam Soker of Technion, Haifa, in Israel.  This paper, which presents a study of ejection velocities in the double-detonation scenario of Type 1a Supernovae was published on 24th January 2024 and is in the folder marked High-Energy Astrophysical Phenomena.

Here is the overlay:

 

 

You can find the full text for this one on the arXiv here.

And that concludes the update.  As you can see, we’re getting a bit more diverse in terms of subject matter, which is nice. There’ll be more next week!