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Four New Publications at the Open Journal of Astrophysics

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

It’s Saturday morning, so once again it’s time for an update of activity at the Open Journal of Astrophysics. This week we have published another batch of four papers, the same number as last week, which takes the count in Volume 7 (2024) up to 64 and the total published altogether by OJAp up to 179.

Before announcing the week’s papers I’ll add three other updates you might find interesting:

  1.  When I looked at NASA/ADS this morning to help construct this post I saw that papers published in OJAp have now garnered over 2500 citations between them;
  2. We had a good response to our recent call for new members of the Editorial Board and have added four new members here;
  3. Last week we received a significant (unsolicited) cash donation from a higher education institution based in Europe to help with our work in Diamond Open Access. If any other organizations or individuals would like to do similar then please contact me!

Now, in chronological order, 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: “Widespread disruption of resonant chains during protoplanetary disk dispersal by Bradley M S Hansen (UCLA), Tze-Yeung Yu (UCLA) and Yasuhiro Hasegawa (JPL), all based in California, USA.  The paper presents a discussion of the effect of a dispersing protoplanetary disk on the evolution of low-mass planets around a Solar mass star.  It was published on 21st July 2024 and is in the folder marked Earth and Planetary 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 “Using A One-Class SVM To Optimize Transit Detection” by Jakob Roche of the University of South Florida, also in the USA (but not in California). This articles discusses the advantages of One-Class Support Vector Machines (SVMs) over Convolutional Neural Networks (CNN) in the context of exoplanet detection. Its in the folder called Instrumentation and Methods for Astrophysics and was published on 25th July 2024.

You can see the overlay here:

 

 

 

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

The next paper, also published on 25th July 2024, is in the folder marked High-Energy Astrophysical Phenomena. Its primary classification on arXiv is General Relativity and Quantum Cosmology (gr-qc), but it is cross-listed on astro-ph so we considered it for publication and had it refereed, with favourable results. It is entitled “What no one has seen before: gravitational waveforms from warp drive collapse” and is by Katy Clough (QMUL, UK), Tim Dietrich (Potsdam, Germany) and Sebastian Khan (Cardiff, UK).  Looking at the title of this paper you might be tempted to dismiss it on the grounds that warp drives are the stuff of science fiction (which they are), but this paper is really a rigorous technical study of the dynamical evolution and stability of spacetimes that violate the null energy condition, inspired by the idea of a warp drive.

Here is the overlay:

 

 

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

Last, published on 26th July 2024, we have a paper with the title “A study of gamma-ray emission from OJ 287 using Fermi-LAT from 2015-2023” by Vibhavasu Pasumarti and Shantanu Desai of the Indian Institute of Technology, Hyderabad, India. It is an investigation of the properties of gamma-ray emission from OJ287 (a BL Lac object) using the Fermi Large Area Telescope (LAT).  This one is also in the folder marked High-Energy Astrophysical Phenomena; here is the overlay

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

That’s all for this week. Stay tuned for another update next week.

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Two New Publications at the Open Journal of Astrophysics

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

My own laptop is still with the menders but I’ve managed to borrow one until I get it back so I don’t get too far behind. Anyway, it’s Saturday morning, and once again 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 54 and the total published by OJAp up to 169.  There was one less arXiv update than usual last week, owing to the holiday on July 4th, so a couple of papers have been delayed.

The first paper of the most recent pair, published on July 3rd 2024,  is “Recovering 21cm Monopole Signals Without Smoothness” by Rugved Pund & Anže Slosar (Stony Brook, NY, USA) and Aaron Parsons (Berkeley, CA, USA) . This paper presents a new method for identifying the ‘Dark Ages’ trough contribution to the monopole of the 21cm radiation background that does not rely on the assumption that the spectrum is smooth. 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, also published on 3rd July, has the title “LtU-ILI: An All-in-One Framework for Implicit Inference in Astrophysics and Cosmology”. There are fifteen authors with primary affiliations as follows: Matthew Ho (IAP, Paris, France), Deaglan J. Bartlett (IAP, Paris, France), Nicolas Chartier (Seoul National University, Korea),  Carolina Cuesta-Lazaro (Cfa, Harvard, USA),  Simon Ding (IAP, Paris, France), Axel Lapel (IAP, Paris, France), Pablo Lemos (Université de Montréal, Canada), Christopher C. Lovell (University of Portsmouth, UK),  T. Lucas Makinen (Imperial College, London, UK), Chirag Modi (Flatiron Institute, NY, USA), Viraj Pandya (Columbia University, NY, USA), Shivam Pandey (Columbia University, NY, USA), Lucia A. Perez (Flatiron Institute, NY, USA), Benjamin Wandelt (IAP, Paris, France),  and Greg L. Bryan (Sorbonne Université, Paris, France).

This paper, which is in the folder marked Instrumentation and Methods for Astrophysics, presents a suite of software for rapid, user-friendly, and cutting-edge inference using machine learning in astrophysics and cosmology. The software can be found on Github here.

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!

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Four New Publications at the Open Journal of Astrophysics

Posted in OJAp Papers, Open Access, The Universe and Stuff with tags , , , , , , , , , , , , on May 11, 2024 by telescoper

It is time yet again for an update of recent activity at the Open Journal of Astrophysics.
This week we have published four papers, which I now present to you. These four take the count in Volume 7 (2024) up to 36 and the total published by OJAp up to 151. I speculated last week that we would probably pass the 150 mark this week, and so we did. We’re still on target to publish around 100 papers this year.
In chronological order, 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 “Ephemeris Matching Reveals False Positive Validated and Candidate Planets from the K2 Mission” by Drake A. Lehmann (U. Wisconsin-Madison, USA) and Andrew Vanderburg (MIT, USA). It presents a description and application of a technique for identifying false positives among candidate exoplanets. The paper was published on 7th May 2024, is in the folder marked Earth and Planetary Astrophysics, and can be found here.
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 “Accuracy requirements on intrinsic alignments for Stage-IV cosmic shear” which is by by Anya Paopiamsap, Natalia Porqueres & David Alonso (Oxford, UK) and Joachim Harnois-Deraps & C. Danielle Leonard (Newcastle, UK). This paper sets about quantifying the permissible level of disagreement between the true intrinsic galaxy alignments and the theoretical models thereof that can be allowed for future Stage-IV cosmic shear surveys. This one is in the folder marked Cosmology and Nongalactic Astrophysics. The paper was published on May 9th 2024 and you can see the overlay here:


The accepted version of this paper can be found on the arXiv here.
The next paper, is in the folder Instrumentation and Methods for Astrophysics and is entitled “Optimal Summary Statistics for X-ray Polarization”. The authors are Jeremy Heyl (Uni. British Columbia, Canada), Denis González-Caniulef (Uni. Toulouse, France) and Ilaria Caiazzo (Caltech, USA). This presents new statistical estimators for use in studies of X-ray polarization, with an analytic discussion of their efficiency. It can be found here and the accepted version can be read on arXiv here. Here is the overlay:

The last paper of this batch is called “B-modes from galaxy cluster alignments in future surveys” and is by Christos Georgiou, Thomas Bakx, Juliard van Donkersgoed and Nora Elisa Chisari, all from Utrecht University in The Netherlands. It presents a discussion of the possible detection of cosmic shear B-modes produced by intrinsic alignments in future galaxy surveys.
Here is the overlay:

You can find the full text for this one on the arXiv here. The primary classification for this one is Cosmology and Nongalactic Astrophysics.
And that ends this week’s update. More next week!

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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.

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New Publication at the Open Journal of Astrophysics

Posted in mathematics, OJAp Papers, Open Access, The Universe and Stuff with tags , , , on November 17, 2023 by telescoper

It’s Friday afternoon but before I collapse, exhausted, into the arms of the weekend I’ll take  the opportunity to announce yet another new paper at the Open Journal of Astrophysics.

The latest paper is the 45th so far in Volume 6 (2023) – just five to go for a half-century – and it’s the 110th altogether. This one was actually published on Tuesday November 14th.

The title is “Marginalised Normal Regression: Unbiased curve fitting in the presence of x-errors” and it’s by Deaglan J. Bartlett (Institut d’Astrophysique de Paris, France) and Harry Desmond (Portsmouth, UK). It sounds like a statistical methods paper, and indeed it is, but remember that there’s a very long historical connection between astronomy and the development of statistical methods for data analysis, and this paper tackles a very longstanding issue: how best to fit curves in the presence of noisy data. This paper presents a new method for doing this, together with applications to cosmological and astrophysical data, and accompanying software. It is in the folder marked Instrumentation and Methods for Astrophysics.

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.

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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 August 30, 2023 by telescoper

Not unexpectedly because of holidays, August has been rather a quiet month at the Open Journal of Astrophysics, but with people returning to work this week business has picked up again and it’s time to announce the last batch (all published this week).

In fact, this week we have published three papers, which I now present to you here. These take the count in Volume 6 (2023) up to 34 and the total published by OJAp up to 99. Who will be the author(s) of the 100th? We will just have to wait and see! I’ll do a special post for whichever paper wins that honour.

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 “Bright common envelope evolution requires jets” by Noam Soker of Technion, Haifa in Israel. This is a discussion of the role of jets that a main sequence secondary star launches as it enters a common envelope evolution (CEE) with a primary giant star. The paper was published on 28th August, is just the fifth item in the folder marked Solar and Stellar Astrophysics and can be found here.

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 “Almanac: MCMC-based signal extraction of power spectra and maps on the sphere” by Elena Sellentin (Leiden), Arthur Loureiro (Stockholm); Lorne Whiteway (UCL); Javier Lafaurie (Leiden); Sreekumar Balan (UCL); Malak Olamaie (York); and Andrew Jaffe & Alan Heavens (Imperial).  This presents a new software tool called Almanac , which uses Hamiltonian Monte Carlo sampling to infer the underlying all-sky noiseless maps of cosmic structures, together with their auto- and cross-power spectra.

This one is  in the folder marked Cosmology and Nongalactic Astrophysics. The paper was also published on 28th August 2023 and 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 paper is in the Instrumentation and Methods for Astrophysics folder. It is entitled “Neural Network Based Point Spread Function Deconvolution For Astronomical Applications” and the authors are: Hong Wang, Sreevarsha Sreejith, Yuewin, Nesar Ramachandra*, Anze Slosar & Shinjae Yoo, all of the Brookhaven National Laboratory (NY) except * who is at the Argonne National Laboratory (IL), all based in the USA. This paper discusses a neural-network based deconvolution algorithm based on Deep Wiener Deconvolution Network (DWDN) and its performance in an astronomical context.

Here is the overlay:

 

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

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Four New Publications at the Open Journal of Astrophysics

Posted in OJAp Papers, Open Access, The Universe and Stuff with tags , , , , , , , on July 19, 2023 by telescoper

Time for an update at the Open Journal of Astrophysics. Owing to a well-deserved holiday by a member of the OJAp team, we were unable to register DOIs and associated metadata for a couple of weeks so refrained from announcing new papers during this period while other functions of the journal continued. Anyway, this week we have caught up with the backlog of four papers, which I now present to you here, all published on 17th July 2023. These four take the count in Volume 6 (2023) up to 26 and the total published by OJAp up to 91.

In no particular order, 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.

“Large-scale power loss in ground-based CMB mapmaking” by Sigurd Naess (Oslo, Norway) and Thibaut Louis (Saclay, France). This one is a discussion of the possible biases introduced by using a data model to create sky maps of CMB temperature fluctuations and is in the folder marked Instrumentation and Methods for 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 primary classification for the next paper paper is Cosmology and Nongalactic Astrophysics and its title is “”The cumulant generating function as a novel observable to cumulate weak lensing information”. The authors are Aoife Boyle (Saclay, France), Alexandre Barthelemy (LMU, Germany), Sandrine Codis (Saclay, France), Cora Uhlemann (Newcastle, UK) & Oliver Friedrich (LMU, Germany). The paper explores the use of the cumulant generating function (CGF), from which the probability density function (PDF) can be obtained, in the context of weak gravitational lensing information.

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.

Also in the folder marked Cosmology and Nongalactic Astrophysics is the third paper “Cosmology with 6 parameters in the Stage-IV era: efficient marginalisation over nuisance parameters” by B. Hadzhiyska (Berkeley, USA), K. Wolz (Trieste, Italy), S. Azzoni (Oxford, UK; Tokyo, Japan), D. Alonso (Oxford, UK), C. García-García (Oxford, UK), J. Ruiz-Zapatero (Oxford, UK) and A. Slosar (Tokyo, Japan). This presents an efficient analytical method to speed up marginalization over nuisance parameters introduced to model systematic effects in large-scale structure data.

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 final paper in this quartet, also in Cosmology and Nongalactic Astrophysics, is “Modeling the Galaxy Distribution in Clusters using Halo Cores” by D. Korytov, E. Rangel, L. Bleem, N. Frontiere, S. Habib, K. Heitmann, J. Hollowed, and A. Pope (all of the Argonne National Laboratory, USA). This presents a new method to speed up numerical simulations using a method of simplifying the handling of substructure in galaxy clusters using halo ‘core-tracking’.

The overlay of this one is here:

 

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

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New Publication at the Open Journal of Astrophysics

Posted in OJAp Papers, Open Access, The Universe and Stuff with tags , , , , , on November 4, 2022 by telescoper

It’s time once again for me to announce new paper at the Open Journal of Astrophysics. The new paper, published last week, is the 15th paper in Volume 5 (2022) and the 63rd in all. The latest publication is entitled “Two-photon amplitude interferometry for precision astrometry” and the authors are Paul Stankus, Andrei Nomerotski and Anže Slosar of Brookhaven National Laboratory (USA) and Stephen Vintskevich (Moscow Institute of Physics & Technology, Russia).

The paper presents a new method for doing interferometry with quantum-mechanically entangled photons and is thus is in the folder marked Instrumentation and Methods for Astrophysics. I don’t know much about this area – and there are many whose baseline opinion is that interferometry is a bit of a fringe topic that is rather complex perhaps needs more visibility in the current phase of its development  (geddit?) – but the physics looks fascinating to me. Amplitude interferometry should be contrasted with the intensity interferometry method of Hanbury Brown and Twiss which I remember learning about as an undergraduate.

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

You can click on the image to make it larger should you wish to do so. The full image used in the overlay is this:

 

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

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New Publication at the Open Journal of Astrophysics

Posted in OJAp Papers, Open Access, The Universe and Stuff with tags , , , , on November 5, 2021 by telescoper

Time to announce yet another publication in the Open Journal of Astrophysics. This one is the 14th paper in Volume 4 (2021) and the 45th in all.

The latest publication is entitled  Ultra Fast Astronomy: Optimized Detection of Multimessenger Transients, and is in the section marked Instrumentation and Methods for Astrophysics.  The authors are Mikhail Denissenya of Nazarbayev University (Kazakhstan) and Eric V. Linder of the University of California at Berkeley (USA).

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

You can find the paper on the Open Journal of Astrophysics site here and can also read it directly on the arXiv here.

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