Archive for Astrophysics of Galaxies

Two New Publications at the Open Journal of Astrophysics

Posted in OJAp Papers, Open Access, The Universe and Stuff with tags , , , , , , , , on July 13, 2024 by telescoper

Another Saturday, another update of the  Open Journal of Astrophysics.  Since the last update we have published two more papers, taking  the count in Volume 7 (2024) up to 56 and the total published by OJAp up to 171.  Both these papers were published on Thursday 11th July 2024.

The first paper of the most recent pair, published on July 3rd 2024,  is “Sunyaev-Zeldovich signatures from non-thermal, relativistic electrons using CMB maps” by Sandeep Kumar Acharya of The Open University of Israel, Ra’anana, Israel.  This article presents a discussion the possible effects of non-thermal electron energy distributions on the form of Sunyaev-Zeldovich distortions and how they might be measured. The paper is in the folder marked Cosmology and NonGalactic Astrophysics.

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

 

 

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

The second paper has the title “On the contribution of dwarf galaxies to reionization of the Universe” and is by Zewei Wu and Andrey Kravtsov of the University of Chicago in the USA. This paper, which is in the folder marked Astrophysics of Galaxies, presents a model of galaxy formation that suggests that radiation from very faint galaxies may contribute significantly to the reionization of the Universe.

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

 

 

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

That concludes this week’s update. No doubt I’ll have more for you next week!

Two New Publications at the Open Journal of Astrophysics

Posted in OJAp Papers, Open Access, The Universe and Stuff with tags , , , , , , , , , , , , , on June 15, 2024 by telescoper

It’s Saturday morning in Barcelona, and time to post another update relating to the  Open Journal of Astrophysics.  Since the last update we have published two more papers, taking  the count in Volume 7 (2024) up to 47 and the total published by OJAp up to 162. We actually accepted four papers last week, but so far only two final versions have appeared on the arXiv.

The first paper of the most recent pair – published on  Friday 14th June – is “Spectroscopic Confirmation of an Ultra-Massive Galaxy in a Protocluster at z 4.9″ . The author list has a strong University of California flavour: Stephanie M. Urbano Stawinski (UC Irvine), M. C. Cooper (UC Irvine), Ben Forrest (UC Davis) , Adam Muzzin (York University, Canada), Danilo Marchesini (Tufts University), Gillian Wilson (UC Merced), Percy Gomez (Keck Observatories, USA), Ian McConachie (UC Riverside), Z. Cemile Marsan (York University, Canada), Marianna Annuziatella (Centro de Astrobiología CSIC-INTA, Spain) and Wenjun Chang (UC Riverside).

This paper presents an investigation of a cluster system involving a massive galaxy using Keck spectroscopy with determination of its redshift and star formation properties. The results pose a challenge for theorists. The paper is in the folder marked Astrophysics of Galaxies.

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

 

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

The second paper, also published on Friday 14th June and has the title “Boil-off of red supergiants: mass loss and type II-P supernovae” by Jim Fuller (Caltech) and  Daichi Tsuna (Caltech, USA and University of Tokyo, Japan). This one, which is in the folder marked Solar and Stellar Astrophysics, discusses A new model for stellar mass loss which predicts that low-mass red supergiants lose less mass than commonly assumed, while high-mass red supergiants lose more.

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

 

 

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

That concludes this week’s update. Will we reach 50 for 20204 next week? Tune in next Saturday to find out!

Three New Publications at the Open Journal of Astrophysics

Posted in OJAp Papers, Open Access, The Universe and Stuff with tags , , , , , , , , , on May 18, 2024 by telescoper

It’s time once more for the usual  Saturday roundup of business at the  Open Journal of Astrophysics. The latest batch of publications consists of three papers, taking the count in Volume 7 (2024) up to 39 and the total published by OJAp up to 154. We’re still on track to publish around 100 papers this year, compared to last year’s 50.

All three of this week’s papers involve use of data from the European Space Agency’s Gaia mission, which is proving an immensely rich resource for astrophysics.

First one up is “Asymmetric Drift Map of the Milky Way Disk Populations between 8 -16 kpc with LAMOST and Gaia datasets” which is by  Xin Li (Nanchong, China), Peng Yang (Chengdu, China) , Hai-Feng Wang (Nanchong, China), Qing Li (Jiangmen, China), Yang-Ping Luo (Nanchong, China), Zhi-Quan Luo (Nanchong, China), Guan-Yu Wang (Nanchong, China). This is a study  of the asymmetric drift, the difference of the local circular speed and the mean rotational speed of the stellar population, for various stellar populations in the Milky Way. It is in the folder marked Astrophysics of Galaxies and was published on Tuesday 14th May 2024.

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

 

 

You can read the paper directly on arXiv here.

The second paper to announce is “On the formation of a 33 solar-mass black hole in a low-metallicity binary” by Kareem El-Badry (Caltech, USA). It discusses theoretical models for the formation of a black hole in a particular binary system discovered in Gaia data.

This one is in the folder Solar and Stellar Astrophysics and was published on 16th May 2024. The overlay looks like this:

 

 

You can read this paper directly on the arXiv here.

The last paper of this batch, also in the in the folder Solar and Stellar Astrophysics, is entitled “Compact Binary Formation in Open Star Clusters II: Difficulty of Gaia NS formation in low-mass star clusters”  and it presents a discussion of the formation of binary neutron stars and black holes found in Gaia data based on their orbital properties. It was published on Friday May 17th 2024 (i.e. yesterday). The authors are Ataru Tanikawa (Fukui University, Japan), Long Wang (Sun-yat Sen University, China) and  Michiko S. Fujii (Tokyo University, Japan).

Here is a screengrab of the overlay:

 

 

To read the accepted version of this on the arXiv please go here.
That’s all for now. Another update next week!

 

 

Three New Publications at the Open Journal of Astrophysics

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

It’s time for the usual  Saturday roundup of business at the  Open Journal of Astrophysics. The latest batch of publications consists of three papers, taking the count in Volume 7 (2024) up to 30 and the total published by OJAp up to 145.

First one up is “Baryonic Imprints on DM Halos: the concentration-mass relation and its dependence on halo and galaxy properties” .  The authors, Mufan Shao and Dhayaa Anbajagane of the University of Chicago, USA, use  a non-linear model informed by simulations to study the imprint of galaxy formation physics on the concentration-mass relationship using various different choices of halo selection criteria. This one is in the folder marked Astrophysics of Galaxies and was published on 24th April 2024.

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

 

You can read the paper directly on arXiv here.

The second paper to announce is “Variability in SSTc2d J163134.1-240100, a brown dwarf with quasi-spherical mass loss” which describes a search for variability in a brown dwarf star known to be losing mass and the implications of the lack thereof for the reason for the outflow therefrom. The authors are Aleks Scholz (St Andrews, UK),  Koraljka Muzic (Lisbon, Portugal), Victor Almendros-Abad (Palermo, Italy), Antonella Natta (DIAS, Ireland), Dary Ruiz-Rodriguez (NRAO, USA), Lucas Cieza (Uni. Diego Portales, Chile), Cristina Rodriguez-Lopez (IAA-CSIC, Granada, Spain)

This one is in the folder Solar and Stellar Astrophysics and was also published on 24th April 2024. The overlay looks like this:

 

You can read this paper directly on the arXiv here.

The last paper of this batch, also in the folder marked Astrophysics of Galaxies, is  entitled “MAGICS I. The First Few Orbits Encode the Fate of Seed Massive Black Hole Pairs”  and is a computational study of the process by which massive black holes are formed by merging smaller seed black holes. It was published on April 26th 2024 (i.e. yesterday). The authors are: Nianyi Chen, Diptajyoti Mukherjee and Tiziana Di Matteo (all Carnegie Mellon University); Yueying Ni (Harvard); Simeon Bird (University of California, Riverside); and Rupert Croft (Carnegie Mellon University). All authors are based in the USA.

Here is a screengrab of the overlay:

 

To read the accepted version of this on the arXiv please go here.
That’s all for now. More news in a week or so!

 

 

Five New Publications at the Open Journal of Astrophysics

Posted in OJAp Papers, Open Access, The Universe and Stuff with tags , , , , , , , , , on April 6, 2024 by telescoper

As promised a couple of days ago, I am taking the opportunity today to announce the batch of papers at the Open Journal of Astrophysics that were paused slightly while we updated our system. This batch includes five papers, which I now present to you here. These five take the count in Volume 7 (2024) up to 25 and the total published by OJAp up to 140. We’re publishing roughly two papers a week these days so we expect publish about 100 this year.

In chronological order, the five papers, 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.

This paper, by Yingtian Chen and Oleg Gnedin of the University of Michigan, is the 21st paper to be published in Volume 7 and the 136th altogether. It is a study of kinematic, chemical and age data of globular clusters from Gaia yielding clues to how the Milky Way Galaxy assembled. Here’s a screenshot of the overlay which includes the abstract. Note the new-style DOI at the bottom left.

You can read the article on arXiv directly here. This paper has a publication date of 20th March 2024, and is in the folder marked Astrophysics of Galaxies.

The second paper is “Generation of realistic input parameters for simulating atmospheric point-spread functions at astronomical observatories” by Claire-Alice Hébert (Stanford), Joshua E. Meyers (Stanford), My H. Do (Cal. State U, Pomona), Patricia R. Burchat (Stanford) and the LSST Dark Energy Science Collaboration. It explores the use of atmospheric modelling to generate realistic estimates of the point-spread function for observational work, especially for the Vera C. Rubin Observatory. This one is in the folder marked Instrumentation and Methods for Astrophysics and was published on 4th April 2024. 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 third paper to announce is “Cosmic Dragons: A Two-Component Mixture Model of COSMOS Galaxies” by William K. Black and August E. Evrard of the University of Michigan (Ann Arbor, USA). This paper was also published on 4th April 2024,  is in the folder Astrophysics of Galaxies and you can see the overlay here:

 

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

The next paper is “High mass function ellipsoidal variables in the Gaia Focused Product Release: searching for black hole candidates in the binary zoo” by Dominick M. Rowan, Todd A. Thompson,
Tharindu Jayasinghe, Christopher S. Kochanek and Krzysztof Z. Stanek of Ohio State University (USA). This paper, in the Solar and Stellar Astrophysics collection, describes a search for massive unseen stellar companions variable star systems found in Gaia data. This one was also published on 4th April 2024.

Here is the overlay:

 

 

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

Last in this batch, but by no means least, published yesterday (5th April 2024), we have a paper “Machine Learning the Dark Matter Halo Mass of Milky Way-Like Systems” by Elaheh Hayati & Peter Behroozi (University of Arizona, USA) and Ekta Patel (University of Utah, USA).  The primary classification for this one is once again Astrophysics of Galaxies and it presents a method for estimating the mass of a galaxy halo using neural networks that does not assume, for example,  dynamical equilibrium:

 

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

As you can see this is quite a diverse collection of papers. Given the increase in submissions in the area of galactic astrophysics we are very happy to welcome another expert in that area to our Editorial Board, in the form of Professor Walter Dehnen of the University of Heidelberg.

Three New Publications at the Open Journal of Astrophysics

Posted in OJAp Papers, The Universe and Stuff with tags , , , , , , , , , , , , , , , , on March 19, 2024 by telescoper

Now that I’m safely back in Barcelona it’s a time for a roundup of the latest business at the  Open Journal of Astrophysics. The latest batch of publications consists of three papers, taking the count in Volume 7 (2024) up to 20 and the total published by OJAp up to 135.

This time the papers are all related, have many authors in common, and have the same first author, Philip F. Hopkins of Caltech. In fact the second and third papers in this batch were accepted well before the first one, but it seemed to make much more sense to publish them together so I held those two back a bit and published all three on 14th March.

The three papers published, 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. You can read these publications directly on arXiv if you wish; you will find them here, here and here.

First one up is “FORGE’d in FIRE: Resolving the End of Star Formation and Structure of AGN Accretion Disks from Cosmological Initial Conditions” in which, using a full cosmological simulation, incorporating radiation and magnetohydrodynamics, the authors study the formation and structure of AGN accretion disks and their impact on star formation. This one is in the folder marked Astrophysics of Galaxies.

The authors (ten from the USA and one from Canada) are Philip F. Hopkins (Caltech), Michael Y. Grudic (Carnegie Observatories), Kung-Yi Su (Harvard), Sarah Wellons (Wesleyan University), Daniel Angles-Alcazar (University of Connecticut & Flatiron Institute), Ulrich P. Steinwandel (Flatiron Institute), David Guszejnov (University of Texas at Austin), Norman Murray (CITA, Toronto, Canada), Claude-Andre Faucher-Giguere (Northwestern University), Eliot Quataert (Princeton), and Dusan Keres (University of California, San Diego or UCSD for short).

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

 

 

The second paper to announce is “FORGE’d in FIRE II: The Formation of Magnetically-Dominated Quasar Accretion Disks from Cosmological Initial Conditions” which is a study of the formation and properties of highly magnetized accretion disks using numerical simulations that include the effects of radiation, magnetic fields, thermochemistry, and star formation.

This one is in the folder High-Energy Astrophysical Phenomena. The authors (ten based in the USA, one fin Canada, and one in New Zealand) are Philip F. Hopkins, Jonathan Squire (University of Dunedin, New Zealand), Kung-Yi Su (Harvard), Ulrich P. Steinwandel (Flatiron Institute), Kyle Kremer (Caltech), Yanlong Shi (Caltech), Michael Y. Grudic (Carnegie Observatories), Sarah Wellons (Wesleyan University), Claude-Andre Faucher-Giguere (Northwestern University), Daniel Angles-Alcazar (University of Connecticut & Flatiron Institute), Norman Murray (CITA, Toronto), and Eliot Quataert (Princeton).

 

The last paper of this batch, also in the folder High-Energy Astrophysical Phenomena, is  entitled “An Analytic Model For Magnetically-Dominated Accretion Disks” and is closely related to the previous one; this particular paper presents an analytic similarity model for accretion disks that agrees remarkably well with the simulations in the previous one. Animations of the simulations referred to in both papers can be found here.

Here is the overlay:

The authors of this one are Philip F. Hopkins, Jonathan Squire, Eliot Quataert, Norman Murray, Kung-Yi Su, Ulrich P. Steinwandel, Kyle Kremer, Claude-Andre Faucher-Giguere, and Sarah Wellons. You can find all their affiliations above.
That’s all for now. More news in a week or so!

 

 

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!

 

Three New Publications at the Open Journal of Astrophysics

Posted in OJAp Papers, Open Access, The Universe and Stuff with tags , , , , , , , , , , , , , , , , , on January 20, 2024 by telescoper

As promised yesterday, it’s time for a roundup of the week’s business at the  Open Journal of Astrophysics. This past week we have published three papers, taking  the count in Volume 7 (2024) up to 4 and the total published by OJAp up to 119. There are quite a few more ready to go as people return from the Christmas break.

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 “Prospects for studying the mass and gas in protoclusters with future CMB observations” by  Anna Gardner and Eric Baxter (Hawaii, USA), Srinivasan Raghunathan (NCSA, USA), Weiguang Cui (Edinburgh, UK), and Daniel Ceverino (Madrid, Spain). This paper, published on 17th January 2024, uses realistic hydrodynamical simulations to probe the ability of CMB Stage 4-like (CMB-S4) experiments to detect and characterize protoclusters via gravitational lensing and the Sunyaev-Zel’dovich effect. This paper is in the category of Cosmology and Nongalactic 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 “SDSS J125417.98+274004.6: An X-ray Detected Minor Merger Dual AGN” and is by Marko Mićić, Brenna Wells, Olivia Holmes, and Jimmy Irwin (all of the University of Alabama, USA).  This presents the discovery of a dual AGN in a merger between the galaxy SDSS J125417.98+274004.6 and dwarf satellite, studied using X-ray observations from the Chandra satellite. The paper was also published on 18th January 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 “Population III star formation: multiple gas phases prevent the use of an equation of state at high densities” and the authors are:  Lewis Prole (Maynooth, Ireland), Paul Clark (Cardiff, UK), Felix Priestley (Cardiff, UK), Simon Glover (Heidelberg, Germany) and John Regan (Maynooth, Ireland). This paper, which presents a comparison of results obtained using chemical networks and a simpler equation-of-state approach for primordial star formation (showing the limitations of the latter) was published on 19th January 2024 and also in the folder marked Astrophysics of Galaxies.

Here is the overlay:

 

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

And that concludes the update. There’ll be more next week!

 

Two New Publications at the Open Journal of Astrophysics

Posted in OJAp Papers, Open Access, The Universe and Stuff with tags , , , , , on December 14, 2023 by telescoper

As anticipated a couple of days ago, it’s now possible to announce another couple of new papers at the Open Journal of Astrophysics. These papers take us up to a total of 49  in Volume 6 (2023) and 114 in total since we started publishing.

It would be nice if we could make it to 50 in Volume 6 (2023), but I have already decided to close the publishing platform from 22nd December until 5th January (inclusive), so there there isn’t much time to get the single needed for our half-century.  While we will not be publishing new papers during this closure, the peer review platform will remain open for submission of new and revised manuscripts and the editorial processes will continue.

Whether or not we make 50 this year, it is worth remarking that 49 is already a significant figure, as it corresponds to the total number of papers we published in the previous three years: 15 (2020); 17 (2021); and 17 (2022). Things are definitely looking up!

Anyway, the first paper of the most recent pair – published on December 8th – is “The Million Quasars (Milliquas) Catalogue, v8”; its primary classification is Astrophysics of Galaxies and the author is Eric Wim Flesch from New Zealand. The Milliquas catalogue includes quasars from the literature to 30 June 2023, including quasars from the DESI-EDR and SDSS-DR18Q surveys.

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

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

The second paper was published on 11th December 2023 and is also in the folder marked Astrophysics of Galaxies.

The authors are all from various institutions in the USA:  Michael Grudić (Carnegie Observatories), Stella Offner (University of Texas at Austin); Dávid Guszejnov (Harvard);  Claude-André Faucher-Giguère (Northwestern University); and Philip F. Hopkins (Caltech).  The paper presents a comparison of full radiative magnetohydrodynamics simulations of the formation of star clusters with simple stochastic modelling showing the limitations of the latter.

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

 

 

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

New Publication at the Open Journal of Astrophysics

Posted in OJAp Papers, Open Access, The Universe and Stuff with tags , , , , on December 12, 2023 by telescoper

I was doing some work on the Open Journal of Astrophysics site and realized that there is a paper we published last week that I haven’t advertised on here yet, so I’m remedying that now.

The paper in question is the 47th so far in Volume 6 (2023)  and it’s the 112th altogether. This one was actually published on Tuesday December 5th. Two further papers are imminent; I’m just waiting for their metadata to be registered with Crossref.

The title of this one is “The SPHINX Public Data Release: Forward Modelling High-Redshift JWST Observations with Cosmological Radiation Hydrodynamics Simulations” and it represents  public data release of Sphinx20, a full box cosmological radiation-hydrodynamics simulation that provides a statistical sample of galaxies for comparison with those observed by JWST. It is in the folder marked Astrophysics of Galaxies.

There are 10 authors: Harley Katz (Oxford, UK); Joki Rosdahl (Lyon, France); Taysun Kimm (Seoul, Korea); Jeremy Blaizot (Lyon, France);  Nicholas Choustikov (Oxford, UK); Marion Farcy  and Thibault Garel (Geneva, Switzerland);  Martin G. Haehnelt (Cambridge, UK); Leo Michel-Dansac (Lyon, France); and Pierre Ocvirk (Strasbourg, France).

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