Archive for white dwarfs

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!