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The KiDS Legacy

Posted in The Universe and Stuff with tags , , , , , , , , on March 30, 2025 by telescoper

What with all the cosmological goings-on of the past couple of weeks – see here, here and here – I quite forgot to mention another important set of results. These are from the final data release Kilo-Degree Survey known as KiDS for short and represent a final analysis of the complete dataset. For those of you not in the know, KiDs is a weak lensing shear tomography survey and its core science drivers are to map the large scale matter distribution in the Universe and constrain the equation of state of Dark Energy. The results can be found in three papers on arXiv, which you can add to your reading list:

As far as I’m concerned, the main result to leap out from the cosmological analysis, which primarily constrains the clumpiness of matter in the universe, expressed by the density parameter Ωm and a fluctuation amplitude σ8 in the combined parameter “S8“, which is constrained almost independently from Ωm. The value obtained for this parameter by KiDS has previously been “in tension” with values from other experiments (notably Planck) ; see here for a discussion. The new results, however, seem consistent with the standard cosmological model. Here is a figure from the last paper in the above list that illustrates the point:

As is often the case, there’s also one of those nice Cosmology Talks videos that discusses this and other aspects of the KiDS Legacy results to which I refer you for more details!

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Weekly update from the Open Journal of Astrophysics – 29/03/25

Posted in OJAp Papers, Open Access, The Universe and Stuff with tags , , , , , , , , , , , on March 29, 2025 by telescoper

It’s time once more for the regular Saturday morning update of papers published 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 32 and the total so far published by OJAp up to 267.

We’re almost at the end of March so I checked the records. In the first three months of last year we published 22 papers, compared to the 32 so far this year.

We were affected by a few gremlins in the works at Crossref this week which delayed some submissions. Since our DOIs are generated and registered with Crossref at the time of publication this delayed some papers a little.  I think these problems are ongoing but I know that the team at Crossref are working on them so expect will be fixed soon.

Anyway, 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 “Gravitational Lensing of Galaxy Clustering” by Brandon Buncher & Gilbert Holder (University of Illinois Urbana Champaign) and Selim Hotinli (Perimeter Institute, Canada). This paper is in the folder marked Cosmology and NonGalactic Astrophysics and it was published on Thursday 27th March 2025. it presents a study of the cross-correlations between lensing reconstruction using galaxies as sources with cosmic shear measurements.

Here is the overlay:

 

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

The second paper of the week is “Reformulating polarized radiative transfer for astrophysical applications. (I) A formalism allowing non-local Magnus solutions” by Edgar S. Carlin (Instituto de Astrofísica de Canarias), Sergio Blanes (Universitat Politcècnica de Valencia) & Fernando Casas (Universitat Jaume I), all in Spain.

It appears in the folder Solar and Stellar Astrophysics. It presents a new family of numerical radiative transfer methods and their potential applications such as accelerating calculations involving Non-Local Thermodynamic Equilibrium. This paper was published on Friday 28th March 2025.

Here is the overlay:

 

 

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

The final paper, also published on Friday 28th March, is in the folder
Cosmology and NonGalactic Astrophysics. The title is “CosmICweb: Cosmological Initial Conditions for Zoom-in Simulations in the Cloud” and the authors are Michael Buehlmann (Argonne National Laboratory), Lukas Winkler (U. Wien), Oliver Hahn (U. Wien), John C. Helly (ICC Durham) and Adrian Jenkins (ICC Durham).

This paper describes a new database and web interface to store, analyze, and disseminate initial conditions for zoom simulations of objects forming in cosmological simulations. The database can be accessed directly here.

Here is the overlay:

 

 

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

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

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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 December 21, 2024 by telescoper

Time for the usual Saturday summary of papers at the Open Journal of Astrophysics. We have published five more papers since the last update a week ago. The count in Volume 7 (2024) is now up to 119 and the total altogether to 234. As I mentioned in a post last week this means we have published more papers this year (2024) than in all previous years put together.

In chronological order, 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.

First one up, published on Wednesday 18th December 2024 is “The picasso gas model: Painting intracluster gas on gravity-only simulations” byby Florian Kéruzoré, L. E. Bleem, N. Frontiere, N. Krishnan, M. Buehlmann, J. D. Emberson, S. Habib, and P. Larsen all of the Argonne National Laboratory, USA.  The paper, which is in the folder marked Cosmology and NonGalactic Astrophysics describes a method using machine learning based on an analytical gas model to predict properties of the intracluster medium.

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, and the first of four published on Wednesday 19th December 2024, “maria: A novel simulator for forecasting (sub-)mm observations” by J. van Marrewijk (ESO, Garching, Germany) and 10 others based in Germany, USA, Norway, France and Italy. This paper describes a multi-purpose telescope simulator that optimizes scanning strategies and instrument designs, produces synthetic time-ordered data, time streams, and maps from hydrodynamical simulations, thereby enabling comparison between theory and observations. This one is in the folder marked Instrumentation and Methods for Astrophysics.

You can see the overlay here:

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

The third paper  is “Detached Circumstellar Matter as an Explanation for Slowly-Rising Interacting Type Ibc Supernovae” by Yuki Takei (Kyoto U., Japan) & Daichi Tsuna (Caltech, USA). This one was also published on 19th December and is in the folder marked High-Energy Astrophysical Phenomena. The overlay is here:

 

 

The officially accepted version can be found on arXiv here.

The fourth paper, also published on 19th December 2024, is called “On the dark matter content of ultra-diffuse galaxies” and was written by Andrey Kravtsov (U. Chicago, USA).  The article discusses the implications of measured velocity dispersions of ultra-diffuse galaxies for models of galaxy formation and is in the folder marked Astrophysics of Galaxies.

The overlay is here

 

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

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

 

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

Finally for this week we have “A new non-parametric method to infer galaxy cluster masses from weak lensing” by Tobias Mistele (Case Western Reserve University, USA) and Amel Durakovic (Czech Academy of Sciences, Czechia). This one was also published on 19th December and is in the folder Cosmology and NonGalactic Astrophysics.  The overlay is here

 

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

That’s in for this week. I will do another update next Saturday only if we have any new papers on Monday. I will be taking a break over Christmas and also preparing Volume 8 (2025) for the new year, so publishing will be suspended from 24th December until 2nd January (inclusive). If you want your paper to be published in 2024 the final version must be on arXiv by Monday 23rd December at the latest, otherwise it will be held over until 2025.

 

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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 November 9, 2024 by telescoper

Once again it’s time for a quick update of activity at the Open Journal of Astrophysics. Since the last update a week ago we have published  four papers, which takes the count in Volume 7 (2024) up to 102 and the total published altogether by OJAp up to 217.   This means not only that we have reached a century for the year but also that so far in 2024 we have published more than double the number of papers that we published in all of 2023. I blogged about the significance of the figure 217 here.

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 generative model for Gaia astrometric orbit catalogs: selection functions for binary stars, giant planets, and compact object companions” by Kareem El-Badry (Caltech, USA), Casey Lam (Carnegie Observatories), Berry Holl & Jean-Louis Halbwachs (U. Geneva), Hans-Walter Rix (MPA Heidelberg, Germany), Tsevi Mazeh (Tel Aviv, Israel) and Sahar Shahaf (Weizmann Institute of Science, Israel). This one is in the folder Solar and Stellar Astrophysics. The paper presents a forward method for estimating the selection function (i.e. the probability of a system with a given set of parameters being included in a catalog). It was published on November 4th 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 second paper to announce, published on 5th November 2024. is “Primordial magnetogenesis in a bouncing model with dark energy” by Marcus V. Bomfim (Rio de Janeiro, Brazil), Emmanuel Frion (Western U. Canada), Nelson Pinto-Neto (Espírito Santo, Brazil), and Sandro D. P. Vitenti (Paraná, Brazil). This paper, in the section on Cosmology and NonGalactic Astrophysics, presents a discussion of the possible generation of magnetic fields on cosmological scales by in a model involving a scalar field coupled to electromagnetism

You can see the overlay here:

 

 

 

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

The third paper, published on 6th November 2024 in the folder marked Astrophysics of Galaxies, is called  “Evidence for large scale compressible turbulence in the ISM of CSWA13, a star-Forming Lensed Galaxy at z = 1.87 with outflowing wind” by Itzhak Goldman (Tel Aviv, Israel). It presents a statistical analysis of the spatial distribution and kinematics of nebular gas with discussion of the nature of the turbulence present.

Here is the overlay

 

 

The final version accepted on arXiv is here.

Last in this batch is “Star formation in the high-extinction Planck cold clump PGCC G120.69+2.66” by Anlaug Amanda Djupvik (Aarhus, Denmark), João L. Yun (Lisbon, Portugal), and Fernando Comerón (ESO, Garching, Germany). It was published on 7th November 2024 in the folder marked Astrophysics of Galaxies. The paper uses imaging and spectroscopy  information to identify sites of star formation in a molecular cloud. This is the overlay:

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

That’s all for now. I will post another update in a 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 August 31, 2024 by telescoper

I am back in circulation after my little break and, since it’s Saturday, I will resume blogging with another report on activity at the  Open Journal of Astrophysics.  Since the last update we have published two more papers, taking  the count in Volume 7 (2024) up to 71 and the total published by OJAp up to 186.  We’ve still got a few in the pipeline waiting for the final versions to appear on arXiv so I expect we’ll reach the 200 mark fairly soon.

The first paper of the most recent pair, published on August 26th 2024,  is “Impact of lensing of gravitational waves on the observed distribution of neutron star masses”  by Sofia Canevarolo, Loek van Vonderen and Nora Elisa Chisari, all of Utrecht University in the Netherlands. This article presents a discussion of the bias in neutron star mass determinations caused by gravitational lensing of the gravitational waves they produceThe 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 “FORGE’d in FIRE III: The IMF in Quasar Accretion Disks from STARFORGE” and was published (in the early hours of the morning) on 29th August 2024. The authors, all based in the USA, are Philip F. Hopkins (Caltech), Michael Y. Grudic (Carnegie Observatories), Kyle Kremer (Caltech), Stella S. R. Offner (UT Austin), David Guszejnov (UT Austin) and Anna L. Rosen (UCSD). This paper, which is in the folder marked Astrophysics of Galaxies, presents a numerical study of star formation and the initial mass function in quasar accretion disks. The previous two papers in this series have also been published in the OJAp: you can find them here and here; images and movies related to this project can be found 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. We still have quite a few papers in the pipeline after the summer lull so I expect I’ll have a larger update for you next week!

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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 10, 2024 by telescoper

It’s Saturday so it’s time once again for another roundup of business at the  Open Journal of Astrophysics. After last week’s summer lull, this week I have three papers to announce, which brings the total we have published so far this year (Vol. 7) to 67 and the total published by OJAp to 182.

First one up, published on 7th August 2024, is “Brightest Cluster Galaxy Offsets in Cold Dark Matter” by Jonathan Katz of Washington University (St Louis, Missouri, USA),  a simulation-based study of the distribution of the position of brightest cluster galaxies relative to the dark matter distribution and its possible use as a cosmological probe.  The authors are Cian Roche (MIT), Michael McDonald (MIT), Josh Borrow (MIT), Mark Vogelsberger (MIT), Xuejian Shen (MIT), Volker Springel (MPA Garching), Lars Hernquist (Harvard), Ruediger Pakmor (Harvard), Sownak Bose (Durham, UK) and Rahul Kannan (York U., Canada). This paper is in the folder marked Astrophysics of Galaxies.

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 present is “LAMOST J1010+2358 is not a Pair-Instability Supernova Relic” by five authors based in the USA: Pierre Thibodeaux (Chicago), Alexander P. Ji (Chicago), William Cerny (Yale), Evan N. Kirby (Notre Dame) and Joshua D. Simon (Carnegie Observatories) .  As the title makes clear, the paper presents arguments against previous claims that a particular star is not a pair-instability supernova relic. This paper is in the folder marked Solar and Stellar Astrophysics. It was published on Friday August 9th 2024.

The overlay looks like this:

 

 

 

You can read this paper directly on the arXiv here.

Last, but by no means least, comes  “A Pilot Search for Gravitational Self-Lensing Binaries with the Zwicky Transient Facility“, results of a trial search for signals of gravitational lensing of one component in a binary system by a compact companion, with a discussion of future prospects for larger surveys. This one, which was also published on 9th August, is in the folder marked High-Energy Astrophysical Phenomena. The authors are Allison Crossland & Eric C Bellm (U. Washington), Courtney Klein (UC Irvine), James R. A. Davenport (U. Washington), Thomas Kupfer (Hamburg Observatory) and Steven L. Groom, Russ R. Laher & Reed Riddle (Caltech).

Here is a screengrab of the overlay:

To read the accepted version of this on the arXiv please go here.

That’s it for this week. I hope to post another update next weekend.

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Two More Euclid ERO videos

Posted in Euclid, Football with tags , , , , on July 1, 2024 by telescoper

I’ve been a bit busy catching up on things since my departure from Barcelona with the result that I almost forgot to post anything today. Fortunately there are two more Euclid Early Release Observations I can share to fill the gap. They’re about 4 minutes apiece, so there’ll be plenty time to watch them while waiting for the VAR operators to make an offside decision during the next European Championship match…

The first is entitled Measuring Luminosity Function for the Perseus Cluster of Galaxies using Euclid ERO data:

The article describing this work can be found on arXiv here; it perhaps makes up for the missing article in the title of the video.

The second one is this, about gravitational lensing and the search for high-redshift galaxies:

The paper for this one can be found on 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 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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Three New Publications at the Open Journal of Astrophysics

Posted in OJAp Papers, Open Access, The Universe and Stuff with tags , , , , , , , , on May 25, 2024 by telescoper

After a very busy and unusual week, it’s time to get back to normal with the usual  Saturday roundup of business at the  Open Journal of Astrophysics. If you want to know how many papers we have published so far this year (Vol. 7), the answer is 42. The total published by OJAp is now 157. We’re still on track to publish around 100 papers this year, possibly more, compared to last year’s 50.

All the members of this week’s trio are in the folder marked Cosmology and Nongalactic Astrophysics, and indeed all three relate in one way or another to the topic of weak gravitational lensing.  All three were published on Wednesday 22nd May 2024.

First one up is “Joint constraints from cosmic shear, galaxy-galaxy lensing and galaxy clustering: internal tension as an indicator of intrinsic alignment modelling error” which is by Simon Samuroff (Northeastern U., USA), Andresa Campos (Carnegie Mellon U., USA), Anna Porredon (Bochum, Germany) and Jonathan Blazek (Edinburgh, UK).   A combined statistical approach to the identification of errors arising in cosmic shear analysis due to intrinsic alignments.

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 present is “A unified linear intrinsic alignment model for elliptical and disc galaxies and the resulting ellipticity spectra” by Basundhara Ghosh (Bangalore, India), with Kai Nussbaumer, Eileen Sophie Giesel & Björn Malte Schäfer (Heidelberg, Germany). It presents a discussion of the physical origin of intrinsic alignments of both elliptical and disk galaxies and the implications for cosmological studies

The overlay looks like this:

 

You can read this paper directly on the arXiv here.

The last paper of this batch is entitled “Neural style transfer of weak lensing mass maps”  and proposes a generative model for the mass-production of weak-lensing maps. The authors are Masato Shirasaki and Shiro Ikeda (both of the University of Tokyo, 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. I will do another update next week.

 

 

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New Publication at the Open Journal of Astrophysics

Posted in OJAp Papers, The Universe and Stuff with tags , , , , , on December 31, 2023 by telescoper

It’s New Year’s Eve and I just remembered that there was a paper at the Open Journal of Astrophysics site that we published before Christmas but that I haven’t yet announced on here, so for the sake of completeness here it is. It takes us to 50 papers published in 2023.

The paper in question is the 50th and final paper  in Volume 6 (2023)  and it’s the 115th altogether. This one was actually published on Friday 22nd December 2023 but owing to the vacations we had to wait a bit to get the metadata registered.

The title of this one is “What are the parities of photon-ring images near a black hole?” and is a discussion of the Fermat potential (also known as the arrival-time surface) in the context of gravitational lensing by strong gravitational fields and the implication for image parities thereby produced. This one is actually listed in General Relativity and Quantum Cosmology (gr-qc, on arXiv) but is cross-listed as Cosmology and Non-galactic Astrophysics so is eligible for publication here in the appropriate folder.

The authors are Ashish Kumar Meena (Ben Gurion University of the Negev, Israel) and Prasenjit Saha (University of Zurich, Switzerland).

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.

And that concludes Volume 6 of the Open Journal of Astrophysics. Roll on Volume 7.

 

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