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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 20, 2024 by telescoper

This week we have published four papers at the Open Journal of Astrophysics, which I now present to you here. These four take the count in Volume 7 (2024) up to 60 and the total published altogether by OJAp up to 175. It is gratifying to see the range of high-quality papers published steadily increasing. We are getting several papers submitted every day 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: “A population of neutron star candidates in wide orbits from Gaia astrometry” by Kareem El-Badry (Caltech, USA) and 12 others based across the world.  The paper presents  a spectroscopic study of neutron star candidates identified using GAIA astrometry to be in wide binary orbits around main sequence stars,  was published on 15th July 2024 and is in the folder marked Solar and Stellar Astrophysics. For more information about this one, see 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 “Systematic Effects in Galaxy-Galaxy Lensing with DESI” and was written by Johannes Ulf Lange (University of Michigan, Ann Arbor, USA) and 58 others, again distributed internationally.  This one reports a study of systematic effects (such as incompleteness and intrinsic alignment) on galaxy-galaxy lensing results from the Dark Energy Spectroscopic Instrument (DESI) survey. This one is in the folder called Cosmology and NonGalactic Astrophysics and was published on 16th July 2024.

You can see the overlay here:

 

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

The next paper is also in the folder called Cosmology and NonGalactic Astrophysics.  It is entitled “Unleashing cosmic shear information with the tomographic weak lensing PDF” and is by by Lina Castiblanco (Newcastle Univresity, UK), Cora Uhlemann (Bielefeld University, Germany), Joachim Harnois-Déraps (Newcastle University, UK) and Alexandre Barthelemy (Ludwig-Maximilians-Universität, Germany). This one was published on 17th July 2024.

Here is the overlay:

 

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

Last but by no means least, published on 18th July 2024, we have a paper  entitled “When to interfere with dark matter? The impact of wave dynamics on statistics“. The primary classification for this one is again Cosmology and Nongalactic Astrophysics and it discusses the imprint of wave-mechanical behaviour, perhaps associated with ultra-light scalar field dark matter on the statistical properties of large-scale structure. The authors are Alex Gough (Newcastle University, UK) and Cora Uhlemann (Bielefeld University, Germany; who also featured in the author list of the previous paper). This is a paper close to my own interests, but because I know both authors well and was the PhD examiner of the first author I thought it best to recuse myself from an editorial role on this one.

 

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.

It did look likely at one stage that we might publish a paper every day last week, but the final version of one other paper didn’t make it onto arXiv in time to be announced on Friday so I will publish that one on Monday.

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Sun-like Stars with Hidden Companions

Posted in OJAp Papers, Open Access, The Universe and Stuff with tags , , , , , , on July 16, 2024 by telescoper

I usually only do updates at weekends about papers published in the Open Journal of Astrophysics but I’m making an exception today because a paper we published yesterday is making some waves that I think are worth propagating. The paper is called “A population of neutron star candidates in wide orbits from Gaia astrometry” and the first author is Kareem El-Badry of Caltech (USA); his institution have put out a press release to go with the paper which you an read for more details. They key point is that these are main sequence stars with (probably) neutron star companions and nobody really knows how such systems formed. The paper is also yet another illustration of the amazingly rich source of discovery data that is the European Space Agency’s Gaia mission.

The press release also contains some snazzy graphics, such as this:

The press release explains

The new study, which includes a team of co-authors from around the world, was published in The Open Journal for Astrophysics. Data from several ground-based telescopes, including the W. M. Keck Observatory on Maunakea, Hawai‘i; La Silla Observatory in Chile; and the Whipple Observatory in Arizona, were used to follow up the Gaia observations and learn more about the masses and orbits of the hidden neutron stars.

It is very gratifying to see one of our papers gaining such traction. It also exemplifies something that has struck me recently. Obviously, when we started the Open Journal of Astrophysics I really had no idea how it would go, but one thing that has surprised me (in a pleasant way) is how many articles we are getting from authors based in high-profile US institutions, such as Caltech, Harvard, Princeton and Berkeley (among others). I always assumed that such institutions were rich enough not to be worried by the cost of Article Processing Charges and, being based in America, the authors would in any case be used to paying page charges for the Astrophysical Journal which has been standard practice for ages. Whatever the reason, it sends a great message to the community to see these leading institutions going via the Diamond Open Access route. I hope this provides even more evidence to persuade even more authors that OJAp is a serious journal!

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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 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!

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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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New Publication at the Open Journal of Astrophysics

Posted in OJAp Papers, Open Access, The Universe and Stuff with tags , , , , , on June 29, 2024 by telescoper

It’s a rainy Saturday morning here in Barcelona, and here’s the last update from the Open Journal of Astrophysics before I depart these shores. In fact there is only one paper to report this week, being  the 52nd paper in Volume 7 (2024)  and the 167th altogether. It was published on June 24th 2024. With six months of the year now over, I predict we will have published about 52×12/6=104 papers by the end of the year.

The title is “Comparing Mass Mapping Reconstruction Methods with Minkowski Functionals” and it  is in the folder marked Cosmology and NonGalactic Astrophysics. The authors are: Nisha Grewal (U. Edinburgh, UK), Joe Zuntz (U. Edinburgh, UK) and Tilman Tröster (ETH Zurich, Switzerland);  the paper is about quantifying the accuracy, precision and efficiency of lensing reconstruction methods using topological characteristics known as Minkowski Fuctionals.

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.

P.S. Since I only had the one paper to publicize this week I took a few minutes to add the overlays to last week’s post, which I couldn’t do at the time because of computer problems.

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A Time Out in Cosmology

Posted in Biographical, LGBTQ+, Talks and Reviews, The Universe and Stuff with tags , on June 26, 2024 by telescoper

Regular readers of this blog – both of them – may recall that earlier this month I gave the inaugural Pride Lecture in the Physics Department at Oxford University. That lecture was given in person but also  streamed via Zoom. This is just an update to let you know that a recording of that stream is now available here should you wish to view it:

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Why Do We Need Simulations for the Euclid Telescope?

Posted in Euclid, The Universe and Stuff with tags , , on June 23, 2024 by telescoper

Until I can get my laptop fixed and/or get a new one, my ability to write blog posts is a bit limited. At least there is a sizeable collection of things to share, including a steady supply of  new videos from the Euclid Consortium like this one:

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Four New Publications at the Open Journal of Astrophysics

Posted in OJAp Papers, The Universe and Stuff on June 22, 2024 by telescoper

Ongoing computer issues mean that this week’s update of activity at the Open Journal of Astrophysics will have to be briefer and with fewer graphics than usual, for which I apologize. During the last week we published four new papers, taking the total so far in 2024 to 51 – so we have already passed last year’s total of 50 – and the total altogether to 166.

The four papers concerned are the following:

https://astro.theoj.org/article/120279-comparing-jet-shaped-point-symmetry-in-cluster-cooling-flows-and-supernovae

(in the folder High-Energy Astrophysical Phenomena, by Noam Soker, of Technion, Haifa, Israel; published on June 20th, arXiv version here)

https://astro.theoj.org/article/120086-repeating-partial-disruptions-and-two-body-relaxation

(in the folder High-Energy Astrophysical Phenomena, by Luca Broggi of the University of Milan, Italy, and six others; published on 21st June, arXiv version here)

https://astro.theoj.org/article/120316-effect-of-the-large-magellanic-cloud-on-the-kinematics-of-milky-way-satellites-and-virial-mass-estimate

(in the folder Astrophysics of Galaxies, by Andrey Kravtsov and Sophia Winney, of the University of Chicago, USA; published on 21st June, arXiv version here)

https://astro.theoj.org/article/120317-semantic-segmentation-of-solar-radio-spikes-at-low-frequencies

(in the folder Solar and Stellar Astrophysics, by Pearse C Murphy, and four others, based in Paris, France, arXiv version here)

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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 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!

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Euclid Updates

Posted in Euclid, The Universe and Stuff with tags , , , , , on June 11, 2024 by telescoper

I’m travelling back to Barcelona today, later than planned because I’ve had a heavy cold that I struggled to shake off and didn’t want to infect fellow passengers on the flight. While I’m in transit I thought I’d share some updates about the European Space Agency’s Euclid mission.

The first thing to share is a piece by Knud Jahnke with news about Euclid’s issue with ice in the optical system. The latest intervention has led to an improvement, but since it is a closed system ice will probably form again – though perhaps not in the same place – and further procedures will probably be necessary in future. In the meantime, though, the survey resumes.

Now for some short videos -three, to be precise – about the Early Release Observations mentioned here. I posted another one in this series here. I think the titles are self-explanatory:

And if that isn’t enough, for those of you who like simulations here is another video about the Euclid Flagship simulation described in this paper.

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