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

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.

#arXiv250308779v2 #arXiv250620654v3 #arXiv250719581v2 #arXiv250920651v1 #arXiv250922523v1 #AstrophysicsOfGalaxies #cosmicDipoles #CosmologyAndNonGalacticAstrophysics #DiamondOpenAccess #EarthAndPlanetaryAstrophysics #GalaxyCluster #galaxyFormation #galaxySurveys #JWST #Kepler #LittleRedDots #MultiplanetSystems #nuclearStarClusters #OpenAccessPublishing #OpenJournalOfAstrophysics #PopulationIIIStars #ramPressureStripping #SDSSC42028 #semiAnalyticGalaxyFormation #TheOpenJournalOfAstrophysics

New Publication at the Open Journal of Astrophysics

It’s Saturday morning once again so it’s time for the usual weekly update of publications at the Open Journal of Astrophysics. This week’s report will be short because, like last week, there is only one paper to report this week, being  the 106th paper in Volume 7 (2024)  and the 221st  altogether. It was published on Thursday 28th November 2024. We have some more papers in the publishing pipeline, which I thought might appear, but they didn’t come out this week possibily because of the Thanksgiving holiday in the USA.

Anyway, The title of the latest paper is “Growth of Light-Seed Black Holes in Gas-Rich Galaxies at High Redshift” by Daxal Mehta, John Regan and Lewis Prole (all of the National University of Ireland, Maynooth*. This paper presents a discussion of the rate of growth of black holes in the early Universe on the basis of simulations run using the Arepo code.

Here is the overlay of the paper containing the abstract:

 

 

You can click on the image of the overlay to make it larger should you wish to do so. You can also find the officially accepted version of the paper on the arXiv here.

That’s all for this week – tune in next Saturday for next week’s update!

*The authors being from Maynooth, I of course recused myself from the editorial process for this article.

#240908326v2 #ArepoCode #AstrophysicsOfGalaxies #blackHoles #galaxies #PopulationIIIStars

Growth of Light-Seed Black Holes in Gas-Rich Galaxies at High Redshift | Published in The Open Journal of Astrophysics

By Daxal Mehta, John A. Regan & 1 more. A discussion of the rate of growth of black holes in the early Universe using the Arepo code.

Regular readers of this blog (both of them) will have noticed that I didn’t post an update of activity at the Open Journal of Astrophysics last weekend. Despite having accepted several papers for publication in the preceding week, no final versions had made it onto the arXiv. We can’t published a paper until the authors post the final version, so that meant a bit of a backlog developed. This week included one day with no arXiv update (owing to a US holiday on Tuesday 8th October) and a major glitch on Crossref on Thursday which delayed a couple, but even so we’ve published six papers which is the most we’ve ever managed in a week. This week saw the publication of our 200th article; the total as of today is 202.  The count in Volume 7 (2024) is now up to 87; we have four papers in the queue for publication so we should pass 90 next week if all goes well.

In chronological order, the six 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, published on Monday 7th October 2024 is “z~2 dual AGN host galaxies are disky: stellar kinematics in the ASTRID Simulation” by Ekaterina Dadiani (CMU; Carnegie Mellon U.) Tiziana di Matteo (CMU), Nianyi Chen (CMU), Patrick Lachance (CMU), Yue Shen (U. Illinois at Urbana-Champaign), Yu-Ching Chen (Johns Hopkins U.), Rupert Croft (CMU), Yueying Ni (CfA Harvard) and Simeon Bird (U. California Riverside) – all based in the USA. The paper, which is in the folder marked Astrophysics of Galaxies describes a numerical study of the morphology of AGN host galaxies containing close pairs of black holes.

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, published on 8th October 2024, is “Origin of LAMOST J1010+2358 Revisited” by S.K. Jeena and Projjwal Banerjee of the Indian Institute of Technology Palakkad, Kerala, India. This paper discusses  the possible formation mechanisms for Very Metal Poor (VMP) stars and the implications for the origin of LAMOST J1010+2358 and is in the folder marked Solar and Stellar Astrophysics.

You can see the overlay here:

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

The third paper is very different in both style and content: “Assessing your Observatory’s Impact: Best Practices in Establishing and Maintaining Observatory Bibliographies” by Raffaele D’Abrusco (Harvard CfA and 14 others; the Observatory Bibliographers Collaboration) and is in the folder marked Instrumentation and Methods for Astrophysics. It presents discussion of the methods used by astronomical observatories to construct and analyze bibliographic databases. The overlay is here:

(This one gave me a rare opportunity to use the library of stock images that comes with the Scholastica platform!) The officially accepted version can be found on arXiv here.

The fourth paper, also published on 8th October 2024, and our 200th publication, is in the folder marked Cosmology and NonGalactic Astrophysics, and is called “CombineHarvesterFlow: Joint Probe Analysis Made Easy with Normalizing Flows“. The authors are Peter L. Taylor, Andrei Cuceu, Chun-Hao To, and Erik A. Zaborowski of Ohio State University, USA. The article presents a new method that speeds up the sampling of joint posterior distributions in the context of inference using combinations of data sets. The overlay is here

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

The fifth paper in this batch is “Estimating Exoplanet Mass using Machine Learning on Incomplete Datasets” by Florian Lalande (Okinawa Institute of Science and Technology), Elizabeth Tasker (Institute of Space and Astronautical Science, Kanagawa) and Kenji Doya (Okinawa); all based in Japan. This one was published on 10th October 2024 in the folder marked Earth and Planetary Astrophysics. It compares different methods for inferring exoplanet masses in catalogues with missing data

 

 

You can find the official accepted version on the arXiv here.

Finally for this week we have “Forecasting the accuracy of velocity-field reconstruction” by Chris Blake and Ryan Turner of Swinburne University of Technology, Melbourne, Australia. This was also published on 10th October 2024 and is in the folder marked Cosmology and NonGalactic Astrophysics. The paper describes a numerical study of the reliability and precision of different methods of velocity-density reconstruction. The overlay is here

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

That’s it for now. We have published six papers, with a very wide geographical spread of authors, and in five of the six astro-ph categories we cover. I think it’s been a good week!

https://telescoper.blog/2024/10/12/six-new-publications-at-the-open-journal-of-astrophysics/

#240606687v2 #ActiveGalacticNuclei #AGN #arXiv231214263v2 #arXiv240100060v3 #arXiv240802643v2 #arXiv240805660v2 #arXiv241006922 #AstrophysicsOfGalaxies #blackHoles #CombineHarvester #CosmologyAndNonGalacticAstrophysics #EarthAndPlanetaryAstrophysics #exoplanets #extrasolarPlanets #inference #InstrumentationAndMethodsForAstrophysics #LAMOSTJ1010 #LAMOSTJ10102358 #largeScaleStructureOfTheUniverse #ObservatoryBibliographies #OpenJournalOfAstrophysics #PopulationIIIStars #SolarAndStellarAstrophysics #TheOpenJournalOfAstrophysics #velocityReconstruction

The Open Journal of Astrophysics

The Open Journal of Astrophysics is an arXiv overlay journal providing open access to peer-reviewed research in astrophysics and cosmology.

We Can't See the First Stars Yet, but We Can See Their Direct Descendants

The first stars in the Universe were enormous, made of primordial hydrogen and helium from the Big Bang. They lived short lives, exploded as supernovae, and seeded nearby nebulae with heavier elements that began the next generation of stars. Our telescopes aren't powerful enough to see them yet, but have astronomers found their direct descendants? The metal-poor stars in the galactic halo seem to show the imprints from those first stars and could offer valuable clues about the first stars in the Universe.

#populationIIIstars

https://www.universetoday.com/163315/we-cant-see-the-first-stars-yet-but-we-can-see-their-direct-descendants/

We Can't See the First Stars Yet, but We Can See Their Direct Descendants

The first stars in the Universe were enormous, made of primordial hydrogen and helium from the Big Bang. They lived short lives, exploded as supernovae, and seeded nearby nebulae with heavier elements that began the next generation of stars. Our telescopes aren't powerful enough to see them yet, but have astronomers found their direct descendants? The metal-poor stars in the galactic halo seem to show the imprints from those first stars and could offer valuable clues about the first stars in the Universe.

Universe Today

We Can't See the First Stars Yet, but We Can See their Direct Descendants

The first stars in the Universe were enormous, made of primordial hydrogen and helium from the Big Bang. They lived short lives, exploded as supernovae, and seeded nearby nebulae with heavier elements that began the next generation of stars. Our telescopes aren't powerful enough to see them yet, but have astronomers found their direct descendants? The metal-poor stars in the galactic halo seem to show the imprints from those first stars and could offer valuable clues about the first stars in the Universe.

#populationIIIstars

http://arxiv.org/abs/2309.07958

Characterising the true descendants of the first stars

The metal-poor stars in the Galactic halo are thought to show the imprints of the first (PopIII) stars, and thus provide a glance at the first episodes of star formation. In this work, we aim at understanding whether all very metal-poor stars formed in environments polluted by PopIII supernovae (SNe) and at what level. With a general parametric model for early metal enrichment, we study the chemical abundances (from C to Zn) of an environment imprinted by a single PopIII SN. We investigate how these abundances depend on the initial mass and internal mixing of PopIII stars, as well as on their SN explosion energy. We then study how subsequent generations of normal (PopII) SNe affect the PopIII chemical signatures. By comparing the observed chemical abundances with our model predictions, we show that stars with [C/Fe]$>+2.5$ form in environments polluted purely by low-energy PopIII SNe ($E_{\rm SN}<2\times 10^{51}$erg). At lower [C/Fe], stars can be imprinted either by PopIII only, or also by normal PopII SNe. The probability of being enriched by PopII SNe increases as [C/Fe] decreases. When PopII stars contribute more to the pollution, they wash out the diverse chemical peculiarities left by the different PopIII SNe, and the chemical dispersion between their descendants decreases. We conclude that C-normal stars ($\rm [C/Fe] \leq +0.7$) have likely been enriched by PopII SNe at a $\geq 50\%$ level and we identify in the abundance scatter a key diagnostic to pinpoint the signature of PopIII SNe.

arXiv.org
Has JWST Finally Found the First Stars in the Univese?

New observations from JWST hint at pockets of new gas in the halo of more evolved galaxies, where these first-generation stars could still form.

Universe Today
Can JWST see Galaxies Made of Primordial Stars?

With a bit of luck, the Webb Space Telescope might be able to see a galaxy full of the first stars.

Universe Today
Scientists Discover Most Distant Star That Humans Have Ever Seen

"Earendel" was spotted about 900 million years after the universe was born, making it by far the most distant star ever seen.