The DECADE #CosmicShear project - a new weak lensing shape catalog of 107 million galaxies: https://arxiv.org/abs/2502.17674 -> UChicago astrophysicists test a new piece of the sky to probe dark matter and dark energy: https://www.eurekalert.org/news-releases/1108575
The DECADE cosmic shear project I: A new weak lensing shape catalog of 107 million galaxies

We present the Dark Energy Camera All Data Everywhere (DECADE) weak lensing dataset: a catalog of 107 million galaxies observed by the Dark Energy Camera (DECam) in the northern Galactic cap. This catalog was assembled from public DECam data including survey and standard observing programs. These data were consistently processed with the Dark Energy Survey Data Management pipeline as part of the DECADE campaign and serve as the basis of the DECam Local Volume Exploration survey (DELVE) Early Data Release 3 (EDR3). We apply the Metacalibration measurement algorithm to generate and calibrate galaxy shapes. After cuts, the resulting cosmology-ready galaxy shape catalog covers a region of $5,\!412 \,\,{\rm deg}^2$ with an effective number density of $4.59\,\, {\rm arcmin}^{-2}$. The coadd images used to derive this data have a median limiting magnitude of $r = 23.6$, $i = 23.2$, and $z = 22.6$, estimated at ${\rm S/N} = 10$ in a 2 arcsecond aperture. We present a suite of detailed studies to characterize the catalog, measure any residual systematic biases, and verify that the catalog is suitable for cosmology analyses. In parallel, we build an image simulation pipeline to characterize the remaining multiplicative shear bias in this catalog, which we measure to be $m = (-2.454 \pm 0.124) \times10^{-2}$ for the full sample. Despite the significantly inhomogeneous nature of the data set, due to it being an amalgamation of various observing programs, we find the resulting catalog has sufficient quality to yield competitive cosmological constraints.

arXiv.org

Weekly Update from the Open Journal of Astrophysics – 25/10/2025

It may be a Bank Holiday weekend here in Ireland, but it’s still time for the usual Saturday update of the week’s new papers at the Open Journal of Astrophysics (although a bit later in the day than usual). Since the last update we have published another five papers, which brings the number in Volume 8 (2025) up to 161, and the total so far published by OJAp up to 396.

This week’s update  is rather unusual because there are four papers in a series (or, more precisely, mathematically speaking, a sequence) all published on the same day (Wednesday October 22nd 2025), in the same folder (Cosmology and NonGalactic Astrophysics), with the same first author (Dhayaa Anbajagane of the University of Chicago), with long author lists and many co-authors in common. These papers all relate to the DECADE cosmic shear project. Instead of doing them one by one, therefore, I’ve decided to put all four overlays together and provide links to all the papers afterwards. As I’m trying to encourage people to follow our feed on the Fediverse via Mastodon (where I announce papers as they are published, including the all-important DOI),  I’ll include links to each announcement there too.



  • The DECADE cosmic shear project I: A new weak lensing shape catalog of 107 million galaxies“, accepted version on arXiv here.
  • The DECADE cosmic shear project II: photometric redshift calibration of the source galaxy sample“, accepted version on arXiv here.
  • The DECADE cosmic shear project III: validation of analysis pipeline using spatially inhomogeneous data“, accepted version on arXiv here.
  • The DECADE cosmic shear project IV: cosmological constraints from 107 million galaxies across 5,400 deg2 of the sky“, accepted version on arXiv here.
  • The fediverse announcements follow:

    Open Journal of Astrophysics

    @[email protected]

    New Publication at the Open Journal of Astrophysics: "The DECADE cosmic shear project I: A new weak lensing shape catalog of 107 million galaxies" by Dhayaa Anbajagane (University of Chicago, USA) et al. (54 authors)

    https://doi.org/10.33232/001c.146158

    October 22, 2025, 12:42 pm 2 boosts 0 favorites

    Open Journal of Astrophysics

    @[email protected]

    New Publication at the Open Journal of Astrophysics: "The DECADE cosmic shear project II: photometric redshift calibration of the source galaxy sample" by Dhayaa Anbajagane (University of Chicago, USA) et al. (53 authors)

    https://doi.org/10.33232/001c.146159

    October 22, 2025, 1:07 pm 2 boosts 0 favorites

    Open Journal of Astrophysics

    @[email protected]

    New Publication at the Open Journal of Astrophysics: "The DECADE cosmic shear project III: validation of analysis pipeline using spatially inhomogeneous data" by Dhayaa Anbajagane (University of Chicago, USA) et al. (53 authors)

    https://doi.org/10.33232/001c.146160

    October 22, 2025, 1:57 pm 1 boosts 0 favorites

    Open Journal of Astrophysics

    @[email protected]

    New Publication at the Open Journal of Astrophysics: "The DECADE cosmic shear project IV: cosmological constraints from 107 million galaxies across 5,400 deg^2 of the sky" by Dhayaa Anbajagane (University of Chicago, USA) et al. (75 authors)

    https://doi.org/10.33232/001c.146161

    October 22, 2025, 2:47 pm 1 boosts 0 favorites

     

    The fifth and final paper for this week is “Clustering of DESI galaxies split by thermal Sunyaev-Zeldovich effect” by Michael Rashkovetskyi of the Harvard-Smithsonian Center for Astrophysics, or CfA for short, and 48 others. This one was published on Wednesday 23rd October in the folder Cosmology and NonGalactic Astrophysics. This paper explores how the clustering properties of galaxies mapped by the Dark energy Spectroscopic Instrument (DESI) relate to the local thermal Sunyaev-Zeldovich emission mapped by the Atacama Cosmology Telescope (ACT). The overlay is here:

    The officially accepted version can be found on arXiv here, and the fediverse announcement is here:

    Open Journal of Astrophysics

    @[email protected]

    New Publication at the Open Journal of Astrophysics: "Clustering of DESI galaxies split by thermal Sunyaev-Zeldovich effect" by Michael Rashkovetskyi (Cfa Harvard-Smithsonian, USA) et al. (49 authors)

    https://doi.org/10.33232/001c.146033

    October 23, 2025, 8:28 am 1 boosts 0 favorites

     

    That concludes the papers for this week. With one week to go and our total at 396, I still think we might reach the 400 total by the end of October.

    #ACT #arXiv250217674v2 #arXiv250217675v2 #arXiv250217676v2 #arXiv250217677v2 #arXiv250820904v2 #AtacamaCosmologyTelescope #cosmicShear #Cosmology #CosmologyAndNonGalacticAstrophysics #DarkEnergySpectroscopicInstrument #DECADECosmicShearProject #DESI #DiamondOpenAccess #DiamondOpenAccessPublishing #galaxyClustering #OpenAccess #OpenJournalOfAstrophysics #TheOpenJournalOfAstrophysics #thermalSunyaevZeldovichEffect #weakGravitationalLensing

    Weekly Update from the Open Journal of Astrophysics – 18/10/2025

    Since the last update we have published four more papers, which brings the number in Volume 8 (2025) up to 156, and the total so far published by OJAp up to 391.

    In the Dark

    Weekly Update from the Open Journal of Astrophysics – 27/09/2025

    It’s Saturday again, so it’s time for a summary of the week’s new papers 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 141, and the total so far published by OJAp up to 376.

    The first paper to report this week is “The Bispectrum of Intrinsic Alignments: Theory Modelling and Forecasts for Stage IV Galaxy Surveys” by Thomas Bakx (Utrecht U., NL), Alexander Eggemeier (U. Bonn, DE), Toshiki Kurita (MPA Garching, DE), Nora Elisa Chisari (Leiden U., NL) and Zvonimir Vlah (Ruđer Bošković Institute, Croatia). This paper was published on Monday 22nd September 2025 in the folder Cosmology and NonGalactic Astrophysics. It studies the bispectrum of intrinsic galaxy alignments, a possible source of systematic errors in extracting cosmological information from the analysis of weak lensing surveys.

    The overlay is here:

    You can make this larger by clicking on it.  The officially accepted version of this paper can be found on the arXiv here.

    The second paper this week, published on Tuesday 23rd September 2025 is “Reanalysis of Stage-III cosmic shear surveys: A comprehensive study of shear diagnostic tests” by Jazmine Jefferson (University of Chicago, USA) and 13 others for the LSST Dark Energy Science Collaboration. It is also in the folder Cosmology and NonGalactic Astrophysics; it describes diagnostic tests on three public shear catalogs (KiDS-1000, Year 3 DES-Y3 s, and Year 3 HSC-Y3); not all the surveys pass all the tests.

    The corresponding overlay is here:

    You can find the officially accepted version on arXiv here.

    The third one this week, published on Wednesday 24th September 2025 in the folder Astrophysics of Galaxies, is “Is feedback-free star formation possible?” by Andrea Ferrara, Daniele Manzoni, and Evangelia Ntormousi (all of the Scuola Normale Superiore, Pisa, Italy). This paper presents an argument that Lyman-alpha radiation pressure strongly limits star formation efficiency, even at solar metallicities, so that a feedback-free star formation phase is not possible without feedback. The overlay is here:

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

    Next we have “Microphysical Regulation of Non-Ideal MHD in Weakly-Ionized Systems: Does the Hall Effect Matter?” by Philip F. Hopkins (Caltech, USA), Jonathan Squire (U. Otago, New Zeland), Raphael Skalidis (Caltech) and Nadine H. Soliman (Caltech). This was also published on Wednesday 24th September 2025, but in the folder Earth and Planetary Astrophysics. It presents an improved treatment of non-ideal effects in magnetohydrodynamics, particularly the Hall effect, and a discussion of the implications for weakly-ionized astrophysical systems.

    The corresponding overlay is here:

     

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

    The fifth, and last, one for this week is “The Local Volume Database: a library of the observed properties of nearby dwarf galaxies and star clusters” by Andrew B. Pace (University of Virginia, USA). This one was published on Friday 26th September (i.e. yesterday) in the folder Astrophysics of Galaxies. It presents a catalogue of positional, structural, kinematic, chemical, and dynamical parameters for dwarf galaxies and star clusters in the Local Volume. The overlay is here:

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

     

    And that concludes the report for this week. I’ll post another update next Saturday.

    #arXiv240506026v2 #arXiv241107424v2 #arXiv250410009v2 #arXiv250503964v3 #arXiv250902566v2 #AstrophysicsOfGalaxies #bispectrum #cosmicShear #CosmologyAndNonGalacticAstrophysics #DarkEnergySurvey #DiamondOpenAccessPublishing #dwarfGalaxies #EarthAndPlanetaryAstrophysics #feedback #HallEffect #intrinsicAlignments #KIDS #LocalGroup #magnetohydrodynamics #OpenAccessPublishing #StarClusters #starFormation #weakGravitationalLensing

    Weekly Update from the Open Journal of Astrophysics – 20/06/2025

    Yesterday (Thursday 19th June 2025) was a national holiday in the USA, which means that no new papers were announced on arXiv today (Friday 20th June). I have therefore decided to bring forwarded the usual weekly update of papers published at the Open Journal of Astrophysics by a day. Since the last update we have published three new papers, which brings the number in Volume 8 (2025) up to 74, and the total so far published by OJAp  is now up to 309.

    The three papers published this week, with their overlays, are as follows. All three were published on Tuesday, June 17th 2025. 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 “Illuminating the Physics of Dark Energy with the Discovery Simulations” by Gillian D. Beltz-Mohrmann (Argonne National Laboratory, USA) and 12 others based in the USA and Spain. This describes new high-resolution cosmological simulations providing a testbed for alternative cosmological probes that may offer additional constraining power beyond Baryon Accoustic Oscillations. It is filed in the folder marked Cosmology and NonGalactic Astrophysics.

    The overlay is here:

    You can read the final accepted version on arXiv here.

    The second paper is in the folder marked Astrophysics of Galaxies. It is “LIGHTS. The extended point spread functions of the LIGHTS survey at the LBT” by Nafise Sedighi (Instituto de Astrofísica de Canarias, Spain) and 15 others based in Spain, USA, Iran, Italy and the UK. It describes the procedure used to construct the extended Point Spread Functions (PSFs) of the LIGHTS survey in images taken with the Large Binocular Cameras (LBCs) of the Large Binocular Telescope (LBT).

    The overlay is here:

     

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

    Finally this week we have “Fast radio bursts as a probe of gravity on cosmological scales” by Dennis Neumann (Leiden University, Netherlands), Robert Reischke (Universität Bonn, Germany), Steffen Hagstotz (Ludwig-Maximilians Universität München, Germany) and Hendrik Hildebrandt (Ruhr University Bochum, Germany). This is about using dispersion measures derived from Fast Radio Bursts (FRBs) in combination with cosmic shear to investigate modified gravity theories, specifically Horndeski gravity. It is in the folder marked 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 revert to the usual schedule for updates next week, and post the next one on Saturday 28th June.

     

    #arXiv240911163v3 #arXiv241020190v2 #arXiv250305947v2 #AstrophysicsOfGalaxies #cosmicShear #Cosmology #CosmologyAndNonGalacticAstrophysics #DiamondOpenAccessPublishing #DiscoverySimulations #fastRadioBursts #HorndeskiGravity #LargeBinocularTelescope #LIGHTSSurvey #OpenJournalOfAstrophysics #PointSpreadFunction #TheOpenJournalOfAstrophysics

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

    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.

    #arXiv240200252v3 #arXiv240207988v2 #arXiv240602693v3 #cosmicShear #cosmologicalZoomSimulations #CosmologyAndNonGalacticAstrophysics #DiamondOpenAccessPublishing #galaxyClustering #GravitationalLensing #radiativeTransfer #SolarAndStellarAstrophysics #TheOpenJournalOfAstrophysics

    It’s Saturday, so it’s time once again for another summary of business at the  Open Journal of Astrophysics. This week I have three papers to announce, which brings the total we have published so far this year (Vol. 7) to 98 and the total published by OJAp to 213.

    First one up, published on Tuesday 29th October 2024, is “Cosmology with shear ratios: a joint study of weak lensing and spectroscopic redshift datasets” by Ni Emas & Chris Blake (Swinburne U., Australia), Rossana Ruggeri (Queensland U, Australia) and Anna Porredon (Ruhr University, Bochum, Germany). This paper is in the folder marked Cosmology and NonGalactic Astrophysics. The paper investigates the use of shear ratios as a cosmological diagnostic, with applications to lensing surveys

    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, also published on Tuesday 29th October 2024, is “Echo Location: Distances to Galactic Supernovae From ASAS-SN Light Echoes and 3D Dust Maps” by Kyle D. Neumann (Penn State), Michael A. Tucker & Christopher S. Kochanek (Ohio State), Benjamin J. Shappee (U. Hawaii), and K. Z. Stanek (Ohio State), all based in the USA. This paper is in the folder marked High-Energy Astrophysical Phenomena and it presents a new approach to estimating the distance to a source by combining light echoes with recent three-dimensional dust maps with application to supernova distances.

    The overlay looks like this:

     

     

    You can read this paper directly on the arXiv here.

    Last, but by no means least, comes  “A deconstruction of methods to derive one-point lensing statistics” by Viviane Alfradique (Universidade Federal do Rio De Janeiro, Brazil), Tiago Castro (INAF Trieste, Italy), Valerio Marra (Trieste), Miguel Quartin (Rio de Janeiro), Carlo Giocoli (INAF Bologna, Italy), and Pierluigi Monaco (Trieste).  Published in the folder marked Cosmology and NonGalactic Astrophysics, it describes a comparative study of different methods of approximating the one-point probability density function (PDF) for use in the statistical analysis of gravitational lensing.

    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, by when we might well have reached a century for this year!

    https://telescoper.blog/2024/11/02/three-new-publications-at-the-open-journal-of-astrophysics-11/

    #arXiv240307313v2 #arXiv240500147v2 #arXiv240714584v2 #cosmicShear #Cosmology #CosmologyAndNonGalacticAstrophysics #DiamondOpenAccess #HighEnergyAstrophysicalPhenomena #shearRatios #supernovae #TheOpenJournalOfAstrophysics #weakGravitationalLensing

    Vol. 7, 2024 | Published by The Open Journal of Astrophysics

    Papers published in 2024