Bullet Cluster (Webb and Chandra Compass Image) ✨
#Cosmology #GalaxyClusters #GravitationalLensing #Multiwavelength
⏩ 3 new pictures from Webb (NASA) https://commons.wikimedia.org/wiki/Special:ListFiles?limit=5&user=OptimusPrimeBot&ilshowall=1&offset=20250701043453
Weekly Update from the Open Journal of Astrophysics – 28/06/2025
It’s Saturday morning again so time for an update of papers published at the Open Journal of Astrophysics. Since the last update we have published eight new papers, which brings the number in Volume 8 (2025) up to 82, and the total so far published by OJAp up to 317. With about half the year gone, we’re on target to published around 160 papers this year.
The 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 “Spectroscopic and X-ray Modeling of the Strong Lensing Galaxy Cluster MACS J0138.0-2155” by Abigail Flowers (University of California at Santa Cruz; UCSZ), Jackson H. O’Donnell (UCSZ), Tesla E. Jeltema (UCSZ), Vernon Wetzell (U. Pennsylvania) & M. Grant Roberts (UCSZ). This artticle, which is in the folder marked Cosmology and NonGalactic Astrophysics, presents a study of the mass distribution and substructure of a galaxy cluster that acts as a gravitational lens for a source galaxy at z=1.95 that contains two supernovae. It was published on 23rd June 2025. The overlay is here:
The officially-accepted version can be found on arXiv here.
“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.
Next one up is in the folder marked Astrophysics of Galaxies. The title is “On the minimum number of radiation field parameters to specify gas cooling and heating functions” and it is by David Robinson & Camille Avestruz (U. Michigan) and Nickolay Y. Gnedin (U.Chicago) and was published on 23rd June 2025. It presents an analysis using machine learning of atomic gas cooling and heating functions computed by the spectral synthesis code Cloudy.
The overlay is here:
You can find the officially-accepted version of the paper on arXiv here.
The thirtd paper is “On the Use of WGANs for Super Resolution in Dark-Matter Simulations” by John Brennan (Maynooth), Sreedhar Balu (U. Melbourne), Yuxiang Qin (ANU), John Regan (Maynooth) and Chris Power (U. Western Australia). This one is also in the folder marked Astrophysics of Galaxies and was also published on Monday 23rd June. It is about using the Wasserstein Generative Adversarial Network (WGAN) model to increase the particle resolution of dark-matter-only simulations of galaxy formation. The overlay is here:
You can find the officially-accepted version of the paper on arXiv here.
Next we have “Cosmic Rays Masquerading as Hot CGM Gas: An Inverse-Compton Origin for Diffuse X-ray Emission in the Circumgalactic Medium” by Philip F. Hopkins (Caltech), Eliot Quataert (Princeton), Sam B. Ponnada (Caltech) and Emily Silich (Caltech), all based in the USA. This one was published on 24th June 2025 in the folder High-Energy Astrophysical Phenomena
You can find the officially-accepted version on arXiv here.
The fifth paper this week is “Compact Binary Formation in Open Star Clusters III: Probability of Binary Black Holes Hidden Inside of Gaia Black Hole Binary” by Ataru Tanikawa (Fukui Prefectural University, Japan), Long Wang (Sun Yat-sen University, China), Michiko S. Fujii (University of Tokyo, Japan), Alessandro A. Trani (Niels Bohr Institute, Denmark), Toshinori Hayashi (Kyoto University, Japan) and Yasushi Suto (Kochi University of Technology, Japan). This one is in the folder marked Astrophysics of Galaxies and was published on Tuesday 24th June. It presents an investigation into whether some Gaia black hole binary systems may in fact involve three black holes, including a pair too compact to be resolved astrometrically. Here is the overlay:
You can find the officially-accepted paper on arXiv here.
Next we have “Rapid identification of lensed type Ia supernovae with color-magnitude selection” by Prajakta Mane (IISER) and Anupreeta More & Surhud More (IUCAA), all based in India. This paper presents an extension of the use of color-magnitude diagrams, used previously as a means to identify lensed supernovae, with applications to LSST-like photometric data. It is in the folder marked Astrophysics of Galaxies and was published on Thursday 26th June.
The officially-accepted version of the article can be found on arXiv here.
The penultimate article this week is: “Cosmic Reionization On Computers: Biases and Uncertainties in the Measured Mean Free Path at the End Stage of Reionization” by Huanqing Chen (U. Alberta, Canada), and Jiawen Fan & Camille Avestruz (U. Michigan, USA). This one is in the folder Cosmology and Nongalactic Astrophysics and was published on 26th June 2025. This paper studies possible systematic effects in computer simulations of cosmic reionization especially when it results from quasar radiation.
The overlay is here:
You can find the officially-accepted version on arXiv here.
Eighth and last paper this week is “Exploring the Core-galaxy Connection” by Isabele Lais de Souza Vitório (U. Michigan) and Michael Buehlmann, Eve Kovacs, Patricia Larsen, Nicholas Frontiere & Katrin Heitmann (Argonne National Laboratory, USA). This one is in the folder Cosmology and Nongalactic Astrophysics and was published on Friday 27th June 2025 (i.e. yesterday).
The overlay is here:
You can find the officially-accepted version on arXiv here.
And that’s all the papers for this week. I do, however, have some more news to pass on. We are delighted to welcome two new recruits to our Editorial Board, Dr Foteini Oikonomou of the Norwegian University of Science and Technology, who specializes in the application of particle physics theories to high-energy astrophysical phenomena, and Dr Heloise Stevance of Oxford University (UK), who specializes in the interface between Machine Learning and Astrophysics.
#arXiv240619446v2 #arXiv240700268v4 #arXiv240703662v4 #arXiv241005372v3 #arXiv241109412v2 #arXiv241219955v2 #arXiv250113056v2 #arXiv250118696v2 #AstrophysicsOfGalaxies #BinaryBlackHoles #CircumgalacticMedium #cosmicRays #CosmicReionization #CosmologyAndNonGalacticAstrophysics #DiamondOpenAccessPublishing #DrHeloiseStevcance #GalacyHalos #galaxyClusters #galaxyFormation #HighEnergyAstrophysicalPhenomena #OJAp #OpenJournalOfAstrophysics #supernovae #TheOpenJournalOfAstrophysics #WAGN
Astronomers discover vast filament of ‘missing’ matter ✨🛰️
▶️ 1 new picture from ESA https://commons.wikimedia.org/wiki/File:Astronomers_discover_vast_filament_of_%E2%80%98missing%E2%80%99_matter_ESA509961_-.png
SCI4301: Dark Matter - Part 1 (April 4, 2022)
PSZ2 G181.06+48.47 - X-Ray Exploration of / Radio Analysis of / Weak-lensing Analysis and Merging Scenario Reconstruction of a Low-mass Cluster with Exceptionally Distant Radio Relics: https://iopscience.iop.org/article/10.3847/1538-4357/adb731 / https://iopscience.iop.org/article/10.3847/1538-4357/adbbb9 / https://iopscience.iop.org/article/10.3847/1538-4357/adbc99 -> #GalaxyClusters on Course to Crash Again, NASA's Chandra Finds: https://chandra.si.edu/photo/2025/g181/ / https://www.nasa.gov/image-article/galaxy-clusters-on-course-to-crash-again-nasas-chandra-finds/
Galaxy Clusters on Course to Crash Again, NASA’s Chandra Finds https://www.nasa.gov/image-article/galaxy-clusters-on-course-to-crash-again-nasas-chandra-finds/ #NASA #ChandraXRayObservatory #Galaxies #GalaxyClusters #MarshallAstrophysics #MarshallSpaceFlightCenter #TheUniverse
Location of Euclid Deep Fields on Gaia and Planck sky map ✨🛰️
#Astronomy #Darkmatter #Galaxies #Galaxies,distant #Galaxy #Galaxyclusters #Gravity #Nebula
⏩ 7 new pictures from ESA https://commons.wikimedia.org/wiki/Special:ListFiles?limit=12&user=OptimusPrimeBot&ilshowall=1&offset=20250320064204
Galaxy clusters are the largest structures in the universe. Protoclusters like SPT2349-56 offer a unique window into this process, allowing astronomers to observe galaxies as they come together in a dense environment.
By comparing ALMA's high-resolution configuration observations with lower-resolution data from ALMA's Compact Array (ACA), and APEX, the team found a significant amount of molecular gas "invisible" in the higher-resolution ALMA images. The ACA detected 75% more CO than the sum of individual sources detected in higher-resolution ALMA data.
This missing gas isn't just a few faint, undetected galaxies. Instead, it appears to be a diffuse reservoir of gas spread throughout the protocluster.
This hidden gas reservoir could be the key to understanding the intense star formation activity observed in SPT2349-56. The presence of so much extra gas extends the star formation fuel, meaning the overall depletion timescale will exceed 400 million years.
SPT2349-56 is an extreme system, producing stars 10.000 times faster than our Milky Way, and these observations have pushed scientists' understanding of galaxy formation and evolution. No simulation or galaxy formation model had previously predicted this overdensity of gas. These findings also suggest that high-resolution ALMA observations, while excellent for studying individual galaxies, may miss a significant gas component in these early clusters. The missing gas may reside in the circum-galactic medium (CGM) or the pre-heated proto-intracluster medium (proto-ICM).
More information at https://www.almaobservatory.org/en/press-releases/alma-founds-hidden-cosmic-fuel/
#ALMA #AtacamaLargeMillimeterSubmillimeterArray #GalaxyClusters #StarFormation
I had the pleasure to be interviewed by Alexandre Morales for France Culture, to talk about the discovery of Quipu, one of the largest known structure of the Universe. It will air tomorrow morning at 6:52.
Here is the press release by the authors of the discovery at MPI Garching https://www.mpg.de/24197951/largest-superstructure-in-the-nearby-universe
#Quipu #QuipuSupercluster #Cosmology #Cosmography #galaxies #galaxyclusters #XrayClusters #ROSAT #CLASSIX #Astronomy #Astrophysics #Astrodon #science #STEM #news #AlexandreMorales #FranceCulture
Phoenix Cluster (Hubble, Chandra, VLA Annotated) ✨
⏩ 2 new pictures from Webb (NASA) https://commons.wikimedia.org/wiki/Special:ListFiles?limit=4&user=OptimusPrimeBot&ilshowall=1&offset=20250214100125
New Simulated Universe Previews Panoramas From NASA’s Roman Telescope https://www.nasa.gov/universe/new-simulated-universe-previews-panoramas-from-nasas-roman-telescope/ #NASA #NancyGraceRomanSpaceTelescope #Astrophysics #DarkEnergy #DarkMatter #Galaxies #GalaxiesStarsBlackHoles #GalaxiesStarsBlackHolesResearch #GalaxyClusters #GoddardSpaceFlightCenter #HighTechComputing #ScienceResearch
Illustration of the Firefly Sparkle Galaxy in the Early Universe (Artist's Concept) ✨
#Galaxies #GalaxyClusters #GravitationalLensing
⏩ 4 new pictures from Webb (NASA) https://commons.wikimedia.org/wiki/Special:ListFiles?limit=5&user=OptimusPrimeBot&ilshowall=1&offset=20241212100528
Found: First Actively Forming Galaxy as Lightweight as Young Milky Way https://science.nasa.gov/missions/webb/found-first-actively-forming-galaxy-as-lightweight-as-young-milky-way/ #NASA #Astrophysics #Galaxies #GalaxyClusters #GoddardSpaceFlightCenter #GravitationalLensing #JamesWebbSpaceTelescopeJWST #ScienceResearch #TheUniverse
New in the #VirtualObservatory: “A2061-A2067 LOFAR images” by Pignataro G.V. et al.
https://cdsarc.cds.unistra.fr/viz-bin/cat/J/A+A/691/A99
#RadioSources #GalaxyClusters
New in the #VirtualObservatory: “Study of EDisCS galaxy clusters” by Cooper J.R. et al.
https://cdsarc.cds.unistra.fr/viz-bin/cat/J/MNRAS/509/5382
#GalaxyClusters #Galaxies #NarrowBandPhotometry #AtomicSpectroscopy
New in the #VirtualObservatory: “LOFAR-MeerKAT AGN in Virgo cluster galaxies” by Spasic A. et al.
https://cdsarc.cds.unistra.fr/viz-bin/cat/J/A+A/690/A195
#ActiveGalacticNuclei #RadioGalaxies #GalaxyClusters
It’s Saturday morning again and time to post an update of activity at the Open Journal of Astrophysics. As last week there are six papers to announce, bringing the count in Volume 7 (2024) up to 93 and the total altogether up to 208.
In chronological order, the six 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 Monday 14th October 2024, is in the folder marked Cosmology and NonGalactic Astrophysics and is called “Backreaction in Numerical Relativity: Averaging on Newtonian gauge-like hypersurfaces in Einstein Toolkit cosmological simulations“. This paper presents a numerical study of the effect of local inhomogeneities on the dynamical evolution of the Universe, i.e. the so-called “backreaction” problem; the authors are Alexander Oestreicher and Sofie Marie Koksbang of the University of Southern Denmark, Odense, Denmark.
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 15th October 2024, is “Weak-Lensing Shear-Selected Galaxy Clusters from the Hyper Suprime-Cam Subaru Strategic Program: II. Cosmological Constraints from the Cluster Abundance” by I-Non Chiu (National Cheng Kung University, Taiwan) and 11 others based in Taiwan, Japan, India and the USA. This paper, which is also in the folder Cosmology and NonGalactic Astrophysics presents constraints on cosmological parameters obtained from a sample of galaxy clusters
You can see the overlay here:
The accepted version of this paper can be found on the arXiv here.
The third paper is “Image formation near hyperbolic umbilic in strong gravitational lensing” by Ashish Kumar Meena (Ben Gurion University, Israel) and Jasjeet Singh Bagla (IISER Mohali, India). It presents a detailed theoretical discussion of a particular form of strong gravitational lensing and its observational consequences; it is in the folder Astrophysics of Galaxies and was published on October 15th 2024.
The overlay is here:
The officially accepted version can be found on arXiv here.
The fourth paper, published on 16th October 2024 and in the folder Astrophysics of Galaxies, is “Weak Gravitational Lensing around Low Surface Brightness Galaxies in the DES Year 3 Data” by N. Chicoine (University of Chicago, USA) et al. (105 authors; DES Collaboration). It presents a demonstration of the viability of using weak gravitational lensing to constrain the halo masses of low surface brightness galaxies.
The overlay is here
You can find the officially accepted version of this paper here.
The fifth paper in this batch is “Imprints of interaction processes in the globular cluster system of NGC 3640” by Ana I Ennis (Waterloo, Canada) and Juan Pablo Caso & Lilia Patricia Bassino (Instituto de Astrofísica de La Plata, Argentina). This one was also published on 16th October 2024 and is in the folder Astrophysics of Galaxies, Here is the overlay
You can find the official accepted version on the arXiv here.
Finally for this week we have “On the nature of the C IV-bearing circumgalactic medium at 𝒛∼𝟏” by Suyash Kumar, Hsiao-Wen Chen, Zhijie Qu & Mandy C. Chen (U. Chicago), Fakhri S. Zahedy (U. North Texas), Sean D. Johnson (Carnegie Observatories), Sowgat Muzahid (IUCAA, India) and Sebastiano Cantalupo (U. Milan Bicocca)
The overlay is here
You can find the officially-accepted version on arXiv here.
That’s it for now. More next week!
https://telescoper.blog/2024/10/19/six-new-publications-at-the-open-journal-of-astrophysics-2/
#240719081v2 #arXiv240300065v2 #arXiv240516826v2 #arXiv240611970v2 #arXiv240803049v1 #arXiv240815824v2 #AstrophysicsOfGalaxies #Backreaction #CarbonIVAbsorbers #CosmologyAndNonGalacticAstrophysics #DarkEnergySurvey #DES #EinsteinToolkit #galaxyClusters #globularClusters #NGC3640 #NumericalRelativity #strongGravitationalLensing #weakGravitationalLensing
For all who missed yesterday's Challenges in Modern Cosmology 2 online workshop, all talks are available on YouTube now, here's mine:
https://www.youtube.com/live/ErHB4Ckzgu8?si=yfBg_bUIP0B4o1yA&t=14602
Galaxy cluster PLCK G165.7+67.0 and SN H0pe Inset (NIRCam) ✨
⏩ 2 new pictures from Webb (NASA) https://commons.wikimedia.org/wiki/Special:ListFiles?limit=3&user=OptimusPrimeBot&ilshowall=1&offset=20241002100243
New in the #VirtualObservatory: “SPT-SZ MCMF catalog” by Klein M. et al.
https://cdsarc.cds.unistra.fr/viz-bin/cat/J/MNRAS/531/3973
#Redshifted #GalaxyClusters #RadioSpectroscopy #Surveys
