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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.

 

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Weekly Update from the Open Journal of Astrophysics – 17/05/2025

Posted in OJAp Papers, Open Access, The Universe and Stuff with tags , , , , , , , , , , , , on May 17, 2025 by telescoper

It’s a lovely Saturday morning in May, and it’s time for the weekly  update of papers published at the Open Journal of Astrophysics. Since the last update we have published four new papers, which brings the number in Volume 8 (2025) up to 59 and the total so far published by OJAp up to 294.

In chronological order of publication, the four 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: “Multi-Phase Thermal Structure & The Origin of the Broad-Line Region, Torus, and Corona in Magnetically-Dominated Accretion Disks” by Philip F. Hopkins (Caltech, USA). This was published on Monday May 12th in the folder Astrophysics of Galaxies. It presents simple accretion disk model that predicts the properties of many features including the dusty torus, broad-line region, continuum emission and coronal gas.

The overlay is here:

You can find the officially accepted version on arXiv here.

Second one up is “Sparsity covariance: a source of uncertainty when estimating correlation functions with a discrete sample of observations in the sky” by Pierre Fleury (U. Montpellier, France). This one was published on Tuesday 13th May 2025 in the folder Cosmology and NonGalactic Astrophysics.  This paper presents a discussion of the uncertainty in cosmological observables caused by discrete sampling and a method to compute the covariances resulting from this.

The overlay is here:

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

The third paper of the week, published on Wednesday May 14th 2025,  is “Dark Matter Particle Flux in a Dynamically Self-consistent Milky Way Model” by Lucijana Stanic, Mark Eberlein, Stanislav Linchakovskyy, Christopher Magnoli, Maryna Mesiura, Luca Morf, Prasenjit Saha (University of Zurich, Switzerland) and Eugene Vasiliev (University of Surrey, UK). This one presents a study of the behaviour of dark matter in an anisotropic model for the Milky Way halo with implications for particle detection rates. It is in the folder Astrophysics of Galaxies.

Here is the overlay:

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

The last paper published this week is “Too fast to be single: Tidal evolution and photometric identification of stellar and planetary companions” by Ilay Kamai and Hagai B. Perets (Technion, Haifa, Israel). This one was published on Friday 16th May 2025 in the folder Solar and Stellar Astrophysics. It presents an analysis of the rotation of stars observed in the Kepler field to identify non-single systems with high spin rates resulting from tidal effects.

Here is the overlay:

The official published version can be found on the arXiv here.

That’s all the papers for this week. I’ll post another update next week.

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Weekly Update from the Open Journal of Astrophysics – 10/05/2025

Posted in OJAp Papers, Open Access, The Universe and Stuff with tags , , , , , , on May 10, 2025 by telescoper

It’s time for another update Saturday morning update of activity at the Open Journal of Astrophysics. After the record-breaking stats described in the last update , this week has been on the slow side with just one paper published. This brings the number in Volume 8 (2025) up to 55 and the total so far published by OJAp up to 290.

The paper to report is “Late-time growth weakly affects the significance of high-redshift massive galaxies” by Qianran Xia & Dragan Huterer (U. Michigan, USA) and Nhat-Minh Nguyen (U. Tokyo, Japan). This paper, which was published on Wednesday 7th May 2025,  is published in the folder Cosmology and NonGalactic Astrophysics. It presents an argument that changes in the growth rate of perturbations at low redshift do not have much effect on predictions of the abundance of lassive galaxies at high redshift.

The overlay is here:

 

You can find the officially accepted version on arXiv here.

That’s all for now. I’ll do another update next week.

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Weekly Update from the Open Journal of Astrophysics – 03/05/2025

Posted in OJAp Papers, Open Access, The Universe and Stuff with tags , , , , , , , , , , , , , , , , , , , on May 3, 2025 by telescoper

Saturday morning once again, and time for another update of papers published at the Open Journal of Astrophysics. It’s been a recording-breaking week: since the last update we have published no fewer than ten papers, which brings the number in Volume 8 (2025) up to 54 and the total so far published by OJAp up to 289.

The first paper to report is “Subspace Approximations to the Focused Transport Equation of Energetic Particles, I. The Standard Form” by B. Kippenstein & A. Shalchi (U. Manitoba, Canada). This paper, which was published on Monday 28th April 2025, presents a hybrid analytical-numerical method to solve the Fokker-Planck equation for the transport of energetic particles. It is published in the folder Solar and Stellar Astrophysics.

The overlay is here:

You can find the officially accepted version on arXiv here.

Next is “The Importance of Subtleties in the Scaling of the ‘Terminal Momentum’ For Galaxy Formation Simulations” by Philip F. Hopkins (Caltech, USA). This presents a technical discussion of issues surrounding the proper modelling of supernova blast waves and their effects in numerical simulations of galaxy formation. It was published on Tuesday 29th April 2025 in the folder Astrophysics of Galaxies. The overlay is here:

The final version can be found on arXic here.

Next one up is “Local variations of the radial metallicity gradient in a simulated NIHAO-UHD Milky Way analogue and their implications for (extra-)galactic studies” by Sven Buder (ANU, Australia), Tobias Buck (U. Heidelberg, Germany), Qian-Hui Chen (ANU) and Kathryn Grasha (ANU). This one was also published on Tuesday 29th April 2025 in the folder Astrophysics of Galaxies. It describes a numerical study of the variation of chemical abundance with radial position in galaxies and the implications of this for galaxy formation. Here is the overlay:

and you can find the final accepted version on arXiv here.

The fourth paper this week is “Zooming In On The Multi-Phase Structure of Magnetically-Dominated Quasar Disks: Radiation From Torus to ISCO Across Accretion Rates” by Philip F. Hopkins (Caltech, USA) and 14 others based in the USA and Canada. This was also published on Tuesday 29th April 2025 in the folder Astrophysics of Galaxies. It presents very detailed numerical study of the structure of magnetized quasar accretion disks. The overlay is here:

You can find the official final version on arXiv here.

Next is “Tomographic halo model of the unWISE-Blue galaxies using cross-correlations with BOSS CMASS galaxies” by Alex Krolewski, Jensen Lawrence, and Will J. Percival (U. Waterloo, Canada). This one was also published on 29th April 2025, which was a busy day(!), but in the folder Cosmology and NonGalactic Astrophysics.  This paper describes using the halo model to create mock samples unWISE-Blue galaxies, applicable to other tomographic cross-correlations between photometric samples and narrowly-binned spectroscopic samples. The overlay is here:

The final version of this one can be found on the arXiv here.

Number six for this week is “StratLearn-z: Improved photo-estimation from spectroscopic data subject to selection effects” by Chiara Moretti (SISSA, Trieste, Italy), Maximilian Autenrieth (Imperial College, UK), Riccardo Serra (SISSA), Roberto Trotta (SISSA), David A. van Dyk (Imperial) and Andrei Mesinger (SNS Pisa, Italy). This was published on Thursday 1st May 2025 in the folder Cosmology and NonGalactic Astrophysics. This one is about estimating photometric redshifts using an approach that relies on splitting the source and target datasets into strata based on estimated propensity score. The overlay is here:

 

The official version can be found on arXiv here.

Next is “The Impact of Galaxy-halo Size Relations on Galaxy Clustering Signals” by Joshua B. Hill and Yao-Yuan Mao (U. Utah, USA). This one was also published on May 2nd 2025 and is in the folder Astrophysics of Galaxies. It discusses the challenge of identifying a specific galaxy halo property that controls galaxy sizes through constraints from galaxy clustering alone. The overlay is here:

You can find the official version of the paper on arXiv here.

The next paper is “Detection of Thermal Emission at Millimeter Wavelengths from Low-Earth Orbit Satellites” by Allen Foster (Princeton, USA) and an international cast of 90 others, which is too many to list individually. This one was also published on Thursday May 1st but is in the folder Instrumentation and Methods for Astrophysics.  The paper discusses the experimental detection of thermal emission from satellites and a discussion of the implications for astrophysical observations, especially time-domain astronomy. The overlay is here:

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

The penultimate paper of this week is “Pseudo-Cls for spin-s fields with component-wise weighting” by David Alonso (U. Oxford, UK). This one was published yesterday (Friday 2nd May 2025).  The paper presents an approach to power spectrum estimation appropriate for data with anisotropic noise properties or for which complicated masks are required.  It can be found in the folder Cosmology and NonGalactic Astrophysics. The overlay is here:

 

The final version of this paper is on arXiv here.

The last paper this week is “The past, present and future of observations of externally irradiated disks” by Planet formation environments collaboration: Megan Allen (U. Sheffield, UK) and 52 others. This paper was published on Friday 2nd May in the folder Solar and Stellar Astrophysics.  It presents a review of research on the effects of the ultraviolet radiation environment on protoplanetary disc evolution and planet formation. The overlay is here:

You can find the final version on arXiv here.

That’s all the papers for this week. I’ll just add that there were quite a few gremlins at Crossref this week, particularly yesterday. I usually do the publishing first thing in the morning but yesterday’s papers were held in a queue for most of the day pending registration. Usually it just takes a few minutes, but for these I had to wait several hours but we got there in the end. Although ten papers is more than we have ever published in a week, we still haven’t had a week in which we’ve published on every working day!

Anyway, that’s all for this week. I’ll post another update next Saturday.

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Weekly Update from the Open Journal of Astrophysics – 26/04/2025

Posted in OJAp Papers, Open Access, The Universe and Stuff with tags , , , , , , , , , , , on April 26, 2025 by telescoper

It’s Satuday morning once again, and time for another update of papers published at the Open Journal of Astrophysics. Since the last update we have published two papers, which brings the number in Volume 8 (2025) up to 44 and the total so far published by OJAp up to 279.

The first paper to report is “Approximating non-Gaussian Bayesian partitions with normalising flows: statistics, inference and application to cosmology” by Tobias Röspel, Adrian Schlosser & Björn Malte Schäfer (Universität Heidelberg, Germany) which was published on April 23rd 2025 in the folder Cosmology and NonGalactic Astrophysics. It is an introduction to normalizing flows – a machine learning technique for transforming distributions – and its application to the extraction of cosmological parameters from supernova data.

The overlay is here:

You can find the officially accepted version on arXiv here.

The other paper this week is “Dwarf Galaxies in the TNG50 Field: connecting their Star-formation Rates with their Environments” by Joy Bhattacharyya & Annika H.G. Peter (Ohio State University, USA) and Alexie Leauthaud (UC Santa Cruz, USA).  This one was published on 24th April 2025 in the older Astrophysics of Galaxies and it studies dwarf galaxies with properties similar to the Large and Small Magellanic Clouds that form in different environments in the TNG50 simulation of the IllustrisTNG project.

The overlay is here:

 

and you can find the final accepted version on arXiv here.

 

That’s all for this week. I’ll have another update next Saturday.

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Weekly Update from the Open Journal of Astrophysics – 19/04/2025

Posted in OJAp Papers, Open Access, The Universe and Stuff with tags , , , , , , , , , , , , , , , , , , , on April 19, 2025 by telescoper

It may be the Easter holiday weekend, but it’s still time for the weekly Saturday morning update of papers published at the Open Journal of Astrophysics. Since the last update we have published five new papers, which brings the number in Volume 8 (2025) up to 42 and the total so far published by OJAp up to 277.

In chronological order of publication, the five 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 “Galaxy Clustering with LSST: Effects of Number Count Bias from Blending” by Benjamin Levine (Stony Brook, NY), Javier Sánchez (STScI, MD), Chihway Chang (Chicago, IL) Anja von der Linden (Stony Brook), Eboni Collins (Dillard, LA), Eric Gawiser (Rutgers, NJ), Katarzyna Krzyżańska (Cornell, NY), Boris Leistedt (Imperial College, UK) on behalf of the LSST Dark Energy Science Collaboration.

This presents a simulation-based study of the effect of source overlaps (blending) on galaxy counts expected for the Vera C. Rubin Legacy Survey of Space and Time (LSST). The paper is in the folder Cosmology and NonGalactic Astrophysics and was published on Monday 14th April 2025. The overlay is here:

 

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

The second paper to announce, published onTuesday 15th April 2025,  “Rapid, strongly magnetized accretion in the zero-net-vertical-flux shearing box” by Jonathan Squire (Otago, New Zealand), Eliot Quataert (Princeton, USA) & Philip F. Hopkins (Caltech, USA). This  paper presents a numerical study of turbulence in a flux shearing box, with discussion of the implications of the results for global accretion disk models and simulations thereof. It was published in the folder High-Energy Astrophysical Phenomena and the overlay is here:

 

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

The third paper of the week, published on Wednesday April 16th 2025,   is “DeepDISC-photoz: Deep Learning-Based Photometric Redshift Estimation for Rubin LSST” by Grant Merz (University of Illinois at Urbana-Champaign, USA) and 13 others (all based in the USA) on behalf of the LSST Dark Energy Science Collaboration. This paper describes adding photometric redshift estimation to the DeepDISC framework for classification objects in co-added images for use with the Vera C. Rubin LSST survey. It can be found in the folder Instrumentation and Methods for Astrophysics.

Here is the overlay:

 

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

The next one to report is “Multidimensional Nova Simulations with an Extended Buffer and Lower Initial Mixing Temperatures” by Alexander Smith Clark and Michael Zingale (Stony Brook University, NY, USA). This paper presents new computer models of classical novae with improved ability to follow nucleosynthesis in the thermonuclear outburst and better treatment of convective transport. This one was also published on Wednesday 16th April 2025 but in the folder Solar and Stellar Astrophysics.

Here is the overlay:

 

The official published version can be found on the arXiv here.

The last paper of the five published this week is “Measurement of the power spectrum turnover scale from the cross-correlation between CMB lensing and Quaia” by David Alonso (Oxford, UK), Oleksandr Hetmantsev (Kyiv, Ukraine), Giulio Fabbian (Cambridge, UK), Anze Slosar (Brookhaven National Laboratory, USA) and Kate Storey-Fisher (Stanford, USA). This is a discussion of using the spatial correlations of quasars and their cross-correlations with cosmic microwave background lensing data to measure a feature corresponding to the matter-radiation equality scale with consequences for cosmological parameter estimation. It was published on Thursday 17th April 2025 in the folder Cosmology and NonGalactic Astrophysics.

The overlay is here:

You can find the officially accepted version on arXiv here.

That’s all the papers for this week. I’ll just add a couple of things.

One is that, although there have been weeks before in which we have published five or more papers, we still haven’t managed to have a week on which we’ve published a paper on every weekday. This week we had two on Wednesday 16th but didn’t have any yesterday (Friday).

The second is that tt has been a while since I last posted a breakdown of the running costs here at the Open Journal of Astrophysics. Today I received an email from Scholastica, our service provider, reminding me our costs will go up shortly (from 22nd April). In the interest of transparency I am passing this information on here.

The new prices will be as follows:

  • Peer Review System annual cost will be $425/year (was $350/year) plus $10 per submission (no change)
  • OA Publishing Platform annual cost will be $1,499/year (was $1,399/year)

Last year we published 120 papers with about 250 submissions. We’re a bit ahead of that this year, so I estimate that our next year’s costs will be a bit less than $5000. That’s still less than the typical APC for a single paper at many journals.

I hope this clarifies the situation.

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Weekly Update at the Open Journal of Astrophysics – 22/03/2025

Posted in OJAp Papers, Open Access, The Universe and Stuff with tags , , , , , , , , , , , , on March 22, 2025 by telescoper

It’s Satuday morning once again, and time for another update of papers published at the Open Journal of Astrophysics. Since the last update we have published two papers, which brings the number in Volume 8 (2025) up to 29 and the total so far published by OJAp up to 264.

The papers we have published this week are connected by the theme of black holes and their role in galaxy formation, which is a very hot topic nowadays!

The first paper to report is “Hawking Radiation from non-evaporating primordial black holes cannot enable the formation of direct collapse black holes” by Jonathan Regan, Marios Kalomenopoulos and Kelly Kosmo O’Neil of the University of Nevada, USA. This paper, which is based on an undergraduate thesis, is a study of the irradiating effects of primordial black holes and a discussion of whether these might influence the subsequent formation of supermassive black holes. It is in the section marked Astrophysics of Galaxies, and was published on Tuesday  18th March.

The overlay is here:

and you can find the final accepted version on arXiv here.

The second paper, which was published on Wednesday 19th March and is also in the folder Astrophysics of Galaxies, is “First Light and Reionization Epoch Simulations (FLARES) – XV: The physical properties of super-massive black holes and their impact on galaxies in the early universe” by Stephen Wilkins & Jussi K. Kuusisto (U. Sussex, UK), Dimitrios Irodotou (Institute of Cancer Research, UK), Shihong Liao (Beijing, China) Christopher C. Lovell (Portsmouth, UK), Sonja Soininen (Insitute of Cancer Research), Sabrina C. Berger (Melbourne, Australia), Sophie L. Newman (Portsmouth, UK), William J. Roper (Sussex), Louise T. C. Seeyave (Sussex), Peter A. Thomas (Sussex) and Aswin P. Vijayan Sussex). This paper uses cosmological hydrodynamical zoom simulations to study the formation of supermassive black holes and their impact on star formation in the early Universe.

Here is the overlay, which you can click on to make larger if you wish:

 

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

That’s all for this week. It’s been a bit frustrating for me as Managing Ediutor, because we have built up a backlog of several papers that were accepted for publication some time ago, but are still waiting for the authors to place the final version on arXiv. I hope these won’t take too long to appear, not least because I would like to clear my workflow on the Scholastica platform!

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Weekly Update from the Open Journal of Astrophysics – 22/02/2025

Posted in OJAp Papers, Open Access, The Universe and Stuff with tags , , , , , , , , , , , , , , , , , , on February 22, 2025 by telescoper

It’s Saturday morning again so it’s time for an update of papers published at the Open Journal of Astrophysics. Things have picked up a bit after a quiet couple of weeks. Since the last update we have published four new papers which brings the number in Volume 8 (2025) up to 18 and the total so far published by OJAp up to 253.

In chronological order of publication, the four 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 in fact our 250th paper:  “Untangling Magellanic Streams” by Dennis Zaritsky (Steward Observatory), Vedant Chandra (Harvard), Charlie Conroy (Harvard), Ana Bonaca (Carnegie Observatories), Phillip A. Cargile (Harvard), and Rohan P. Naidu (MIT), all based in the USA. This paper is in the folder marked Astrophysics of Galaxies and it reports on spectroscopic study aimed at teasing out the stellar populations of different strands of the Magellanic Stream. It was published on Tuesday 18th February 2025. Here is the overlay:

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

The second paper of the week  is “Compressed ‘CMB-lite’ Likelihoods Using Automatic Differentiation” by Lennart Balkenhol (Institut d’Astrophysique de Paris, France) which was one of two papers published on Wednesday 19th February. It appears in the folder Cosmology and Nongalactic Astrophysics and it describes an implementation of the CMB-lite framework relying on automatic differentiation to reduce the computational cost of the lite likelihood construction.  The overlay is here:

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

The next paper, also published on Wednesday 19th February in the folder Cosmology and Nongalactic Astrophysics is “Bayesian distances for quantifying tensions in cosmological inference and the surprise statistic” by Benedikt Schosser (Heidelberg, Germany), Pedro Riba Mello & Miguel Quartin (Rio de Janeiro, Brazil) and Bjoern Malte Schaefer (Heidelberg).  It presents a discussion of statistical divergences applied to posterior distributions following from different data sets and their use in quantifying discrepancies or tensions.

Here is the overlay:

The official published version can be found on the arXiv here.

Finally in this batch we have “Precise and Accurate Mass and Radius Measurements of Fifteen Galactic Red Giants in Detached Eclipsing Binaries” by Dominick M. Rowan,  Krzysztof Z. Stanek,  Christopher S. Kochanek & Todd A. Thompson (Ohio State University), Tharindu Jayasinghe (independent researcher),  Jacqueline Blaum (UC Berkeley),  Benjamin J. Fulton (NASA/Caltech),  Ilya Ilyin (AIP Potsdam, Germany),  Howard Isaacson, Natalie LeBaron  &  Jessica R. Lu (UC Berkeley), and  David V. Martin (Tufts University, USA).  This paper was published on Thursday 20th February 2025 in the folder Solar and Stellar Astrophysics and it presents a compilation of mass and readius measurements of red giant stars obtained using spectroscopic measurements together with light curves and the eclipsing binary models obtained using PHOEBE.

The overlay is here:

You can find the “final” version on arXiv here.

That’s all for this week. I’ll do another update next Saturday.

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Weekly Update from the Open Journal of Astrophysics – 01/02/2025

Posted in OJAp Papers, Open Access, The Universe and Stuff with tags , , , , , , , , , , , , , , , , , , on February 1, 2025 by telescoper

It’s Saturday morning, so once again it’s time for an update of papers published at the Open Journal of Astrophysics. There were no papers to report last week but since the last update we have published four new papers, which brings the number in Volume 8 (2025) up to 11 and the total so far published by OJAp up to 246.

In chronological order of publication, the four 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  “A halo model approach for mock catalogs of time-variable strong gravitational lenses” by Katsuya T. Abe & Masamune Oguri (Chiba U, Japan), Simon Birrer & Narayan Khadka (Stony Brook, USA), Philip J. Marshall (Stanford, USA), Cameron Lemon (Stockholm U., Sweden), Anupreeta More (IUCAA, India), and the LSST Dark Energy Science Collaboration. It was published on 27th January 2025 in the folder marked Cosmology and NonGalactic Astrophysics. The paper discusses how to generate mock catalogs of strongly lensed QSOs and Supernovae on galaxy-, group-, and cluster-scales based on a halo model that incorporates dark matter halos, galaxies, and subhalos.

 

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

This paper, also published on Monday 27th January 2025, but in the folder Astrophysics of Galaxies, is “The Soltan argument at redshift 6: UV-luminous quasars contribute less than 10% to early black hole mass growth” by Knud Jahnke (MPI Heidelberg, Germany). This paper presents an argument that almost all growth of supermassive black hole mass at z>6 does not take place in UV-luminous quasars.

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, published on 29th January 2025 in the folder Cosmology and NonGalactic Astrophysics, is “A Heavy Seed Black Hole Mass Function at High Redshift – Prospects for LISA” by Joe McCaffrey & John Regan (Maynooth U., Ireland), Britton Smith (Edinburgh U., UK), John Wise (Georgia Institute of Technology, USA), Brian O’Shea (Michigan State U., USA) and Michael Norman (University of California, San Diego). This is a numerical study of the growth rates of massive black holes in the early Universe and implications for their detection via gravitational wave emission.

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 “Forecasting the Detection of Lyman-alpha Forest Weak Lensing from the Dark Energy Spectroscopic Instrument and Other Future Surveys” by Patrick Shaw & Rupert A. C. Croft (Carnegie Mellon U., USA) and R. Benton Metcalf (U. Bologna, Italy). This paper, published on January 30th 2025, is about extending the applicationof  Lyman-α forest weak gravitational lensing to lower angular source densities than has previously been done, with forecasts for future spectral surveys. It is in the folder marked Cosmology and NonGalactic Astrophysics.

The overlay is here

 

You can find the accepted version on arXiv here.

Incidentally, we currently have 121 papers under review, including 81 under a revise and resubmit request.

That’s all for this week. I’ll do another update next Saturday.

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2024 in Retrospect

Posted in Barcelona, Biographical, Cardiff, Maynooth with tags , , , , , on December 31, 2024 by telescoper 
What we call the beginning is often the end
And to make an end is to make a beginning.
The end is where we start from.

T. S. Eliot, from Little Gidding, the last of the Four Quartets.

I wasn’t really planning on posting a retrospective of the year 2024, but the rain is pouring down outside so I’ve decided to use up a bit of time before going out in the hope that the rain stops.

The past year has been very busy with significant life events. One particular highlight has to be a wonderful once-in-a-lifetime trip to Sydney in February. I don’t know if I’ll ever get the chance to visit Australia again, but if I do I’ll take it! Shortly after returning from that trip I went back to Barcelona until the summer, leaving briefly for visits to Rome (Euclid Consortium Meeting), Valencia (Department Colloquium), Newcastle (to do a PhD examination) and Oxford (to give the inaugural Pride talk at the Department of Physics).

Unfortunately, at that point my laptop gave up the ghost so I had to come back to Maynooth a little earlier than planned to salvage what was on it and get a new one. And so ended my sabbatical. I’d like to take the opportunity again to thank everyone at the Universities of Barcelona and Sydney for making me feel so welcome and, of course, to Maynooth for granting me a full-year sabbatical in the first place.

As well as giving me some time for my own research, the year saw significant progress with the Open Journal of Astrophysics, both in terms of numbers of papers published (120 in 2024) but also some much-needed work on automation and an increase in the size of the Editorial Board. It’s hard to predict what will happen in 2025, but I’m glad that a significant number of members of the astrophysics community seem to be regarding OJAp as a viable avenue for communicating their results.

I will also mention – for those that care – that the Open Journal of Astrophysics is now listed in Scopus, but all the numbers they have published about the journal are inaccurate. I have spent months trying to get them to correct the figures but, although they have admitted errors, they have failed to do so. My next step will be to take legal action against Scopus (which is based in The Netherlands) under the Dutch Civil Code.

The big event workwise at Maynooth was the merger of the Departments of Theoretical Physics and Experimental Physics into a single Department of Physics. So far this has been largely paper exercise. What will result from it in the long term remains to be seen. I was given two new modules to teach last Semester and have another new one next Semester (as well as one I’ve done before). Although this made for a heavy workload, it wasn’t as bad as what happened after the only other sabbatical I’ve had in my career. I got a one Semester sabbatical when I was at Nottingham, but the Department simply moved my first-semester teaching to the second semester in addition to what had already been allocated for the second, so I had a double teaching load when I got back!

There has been a significant change in my personal circumstances too. During 2024 I finally completed the sale of my former home in Pontcanna, Cardiff. I had intended to do this years ago, but the pandemic and subsequent workload issues made it difficult to travel and sort this matter out. In the meantime bought my house in Maynooth with a mortage so I owned two properties, one of which was empty for much of the time. After much stopping and starting, and being badly let down by more than one prospective buyer, the Cardiff house is now sold. I now feel much less delocalised. I also felt very rich when the proceeds hit my bank account, but only briefly. I used a big chunk to pay off my mortgage and put the rest into fixed-term investments for retirement.

Anyway, writing about Sydney reminded me that there are parts of the world in which it is 2025 already, so let me end with a “Happy New Year” and a few interesting numerological facts about the number 2025:

P.S. It’s still raining.

P.P.S. Athbhliain faoi shéan agus faoi mhaise daoibh! 

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