Archive for TESS

Weekly Update from the Open Journal of Astrophysics – 19/07/2025

Posted in OJAp Papers, Open Access, The Universe and Stuff with tags , , , , , , , , , , , , , , , , , , , , , , , , , , on July 19, 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 six new papers, which brings the number in Volume 8 (2025) up to 98, and the total so far published by OJAp  up to 333. I expect we’ll pass the century for this year sometime next week.

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 “Reconstructing Galaxy Cluster Mass Maps using Score-based Generative Modeling” by Alan Hsu (Harvard), Matthew Ho (CMU), Joyce Lin (U. Wisconsin-Madison), Carleen Markey (CMU), Michelle Ntampaka (STScI), Hy Trac (CMU) & Barnabás Póczos (CMU), all based in the USA. This paper was published on 14th July 2025 in the folder Cosmology and NonGalactic Astrophysics. It presents a diffusion-based generativbe AI model for reconstructing density profiles for galaxy clusters from observational data.

The overlay is here:

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

The second and third papers are related. They were both published on 14th July in the folder Cosmology and NonGalactic Astrophysics.

The first of the pair is “J-PLUS: Tomographic analysis of galaxy angular density and redshift fluctuations in Data Release 3. Constraints on photo-z errors, linear bias, and peculiar velocities” by Carlos Hernández-Monteagudo (IAC, Tenerife, Spain) and 21 others. This presents an analysis of the Javalambre Photometric Local Universe Survey (J-PLUS) in redshift slices with a discussion of prospects for extracting cosmological information. The overlay is here:

 

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

The second of this pair is “The J-PLUS collaboration. Additive versus multiplicative systematics in surveys of the large scale structure of the Universe” by Carlos Hernández-Monteagudo (IAC) and 21 others (the same authors as the previous paper).  This paper presents an analysis of systematic effects in the Javalambre Photometric Local Universe Survey (J-PLUS), and a new model for handling such errors in this and other cosmological surveys. The overlay for this paper is here:

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

The fourth paper this week is “Why Machine Learning Models Systematically Underestimate Extreme Values” by Yuan-Sen Ting (Ohio State University). This one was published on July 16th in the folder marked Instrumentation and Methods for Astrophysics.  This paper presents a theoretical framework for understanding and addressing a bias that suppresses the dynamic range of variables in applications of machine learning to astronomical data analysis. Here is the overlay:

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

The penultimate article for this week is “Bridging Machine Learning and Cosmological Simulations: Using Neural Operators to emulate Chemical Evolution” by Pelle van de Bor, John Brennan & John A. Regan (Maynooth University) and Jonathan Mackey (Dublin Institute for Advanced Studies), all based in Ireland. This paper uses machine learning, in the form of neural operators, to emulate the Grackle method of solving non-equilibrium chemistry equations in cosmological hydrodynamic simulations and was published on 16th July also in the folder Instrumentation and Methods for Astrophysics. The overlay is here:

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

The last article published this week is “Astronomical Cardiology: A Search For Heartbeat Stars Using Gaia and TESS” by Jowen Callahan, D. M. Rowan, C. S. Kochanek and K. Z. Stanek (all of Ohio State University, USA). This paper presents a study of a sample of 112 new spectroscopic binaries called hearbeat stars (because their light curves resemble electrocardiagrams). It was published on 16th July 2025 in the folder marked Solar and Stellar Astrophysics. 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.

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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!

 

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