Abstracts of Interest

Selected by: Simon Lee

Abstract: 2504.16881
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Title:Fermi-LAT and FAST observation of the gamma-ray binary HESS J0632+057

Authors:Yanlv Yang, Dengke Zhou, Zihao Zhao, Jian Li, Diego F. Torres, Pei Wang

Using 15 years of data from the Fermi Large Area Telescope (Fermi-LAT), we performed a comprehensive analysis on the gamma-ray binary HESS J0632+057. Its spectrum in 0.1-300 GeV band is well described by a power law model with an index of $2.40\pm0.16$ , leading to an energy flux of (5.5 $\pm$ 1.6 $)\times$ 10 $^{-12}$ erg cm $^{-2}$ s $^{-1}$ . The GeV Spectral Energy Distribution (SED) of HESS J0632+057 hints for a spectral turn-over between $\sim$ 10-100 GeV. Orbital analysis reveals a flux enhancement during the phase range of 0.2-0.4, consistent with the X-ray and TeV light curves, indicating an origin of a common particle population. We carried out six deep radio observations on HESS J0632+057 with the Five-hundred-meter Aperture Spherical Telescope (FAST), evenly distributed across its orbit, reaching a detection sensitivity of 2 $\mu$ Jy. However, no radio pulsation was detected within these observations. The absence of radio pulsation may be attributed to the dense stellar wind environment of HESS J0632+057.

Abstract: 2504.17034
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Title:An extremely soft and weak fast X-ray transient associated with a luminous supernova

Authors:W.-X. Li, Z.-P. Zhu, X.-Z. Zou, J.-J. Geng, L.-D. Liu, Y.-H. Wang, R.-Z. Li, D. Xu, H. Sun, X.-F. Wang, Y.-W. Yu, B. Zhang, X.-F. Wu, Y. Yang, A. V. Filippenko, X.-W. Liu, W.-M. Yuan, D. Aguado, J. An, T. An, D. A.H. Buckley, A. J. Castro-Tirado, S.-Y. Fu, J. P.U. Fynbo, D. A. Howell, J.-W. Hu, S.-Q. Jiang, A. Kumar, J. -R. Mao, J. R. Maund, X. Liu, B. Mockler, A. Moskvitin, M. Andrews, C. R. Bom, T. G. Brink, K. Chatterjee, Y. Chen, H.-Q. Cheng, J. Cooke, J.L. Dai, G.-W. Du, N. Erasmus, Y. Fang, J. Farah, V. Goranskij, M. Gritsevich, M. Gu, Z. Guo, E. Hsiao, Y.-D. Hu, Y.-L. Hua, W. Jacobson-Galán, S.-M. Jia, C.-C. Jin, M. M. Kasliwal, C. D. Kilpatrick, B. Kumar, W.-H. Lei, C.-K. Li, D.-Y. Li, L.-P. Li, Z.-X. Ling, Q.-C. Liu, Y. Liu, Y.-Q. Liu, A. López-Oramas, O. Maslennikova, C. McCully, I. Monageng, M. Newsone, E. Padilla Gonzalez, H.-W. Pan, H.-W. Peng, G. Pignata, F. Poidevin, S. B. Potter, I. Pérez-Fournon, L. Santana-Silva, A. Santos, C.-Y. Song, F.-F. Song, O. Spiridonova, N.-C. Sun, X.-J. Sun, G. Terreran, L.-Z. Wang, L.-F. Wang, B.-T. Wang, Z.-Y. Wang, G.-L. Wu, D.-F. Xiang, H.-F. Xiao, Y.-F. Xu, S.-J. Xue, S.-Y. Yan, Y.-P. Yang, L.-X. Yu, Y.-H. Zhang, Y.-H. Zhang et al. (5 additional authors not shown)

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Long gamma-ray bursts (LGRBs), including their subclasses of low-luminosity GRBs (LL-GRBs) and X-ray flashes (XRFs) characterized by low spectral peak energies, are known to be associated with broad-lined Type Ic supernovae (SNe Ic-BL), which result from the core collapse of massive stars that lose their outer hydrogen and helium envelopes. However, the soft and weak end of the GRB/XRF population remains largely unexplored, due to the limited sensitivity to soft X-ray emission. Here we report the discovery of a fast X-ray transient, EP250108a, detected by the Einstein Probe (EP) in the soft X-ray band at redshift $z = 0.176$ , which was followed up by extensive multiband observations. EP250108a shares similar X-ray luminosity as XRF\,060218, the prototype of XRFs, but it extends GRBs/XRFs down to the unprecedentedly soft and weak regimes, with its $E_{\rm peak} \lesssim 1.8\,\mathrm{keV}$ and $E_{\rm iso} \lesssim 10^{49}\, \mathrm{erg}$ , respectively. Meanwhile, EP250108a is found to be associated with SN\,2025kg, one of the most luminous and possibly magnetar-powered SNe Ic-BL detected so far. Modeling of the well-sampled optical light curves favors a mildly relativistic outflow as the origin of this event. This discovery demonstrates that EP, with its unique capability, is opening a new observational window into the diverse outcomes of death of massive stars.

Comments:

54 pages, 10 figures, submitted

Abstract: 2504.17024
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Title:Hunting Star-Forming Galaxies in the Gamma-Ray Domain

Authors:P. Kornecki, J. Biteau, C. Boisson, P. Cristofari

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Abstract:Context. Star-forming galaxies emit {\gamma}rays with relatively low luminosity, but the study of their emission is no less captivating. While it is known that their {\gamma}-ray luminosity in the GeV band is strongly linked to their star formation, the origin of their emission at higher energies remains uncertain due to limited observations. Aims. Our aim is to assemble the largest possible sample of star-forming galaxies with potential detectability by the new-generation of Cherenkov telescopes. Methods. To achieve this, we compile a comprehensive sample of galaxies, including those previously detected by Fermi-LAT in the GeV energy range as well as a larger sample of star-forming galaxies in the Local Volume that have been cataloged in the near-infrared band. We estimate their {\gamma}-ray flux assuming a proportional relationship with their star formation rate, and then select the brightest candidates. The predicted spectra in the TeV band are derived using a simple empirical model normalized to the star formation rate and a model based on extrapolating the latest Fermi-LAT data to higher energies. The ground-based detectability of {\gamma}-ray emission from these sources is assessed through a comparison to the most recent instrument response functions. Results. Our investigation reveals that almost a dozen star-forming galaxies may be detectable by upcoming {\gamma}-ray telescopes. Conclusions. The observation of numerous star-forming galaxies in the TeV band is a fundamental piece of the panchromatic puzzle for understanding the physics inside these galaxies. The significant increase in the number of galaxies that can be studied in detail in the near future, particularly with the Cherenkov Telescope Array Observatory, promises a major step forward in the study of the conditions of acceleration and transport of cosmic rays in nearby extragalactic environments.

Abstract: 2504.17478
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Title:Prospective sensitivity of CTA on detection of evaporating primordial black holes

Authors:Chen Yang, Xin Zhang

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As the lifetime of a black hole decreases, the energy of the Hawking radiation it emits increases, ultimately culminating in its disappearance through a powerful burst of gamma rays. For primordial black holes (PBHs) with an initial mass of $\sim 5\times10^{14}$ g, their lifespans are expected to end in the present epoch. Detecting such PBH bursts would provide compelling evidence of their existence. The Cherenkov Telescope Array (CTA) has the potential to observe these bursts at the high-energy end of the gamma-ray spectrum. To investigate this possibility, we conduct a study to evaluate the sensitivity of CTA to the local burst rate density of PBHs. Our results suggest that during a 5-year observational campaign, CTA could exclude a local burst rate density exceeding $\sim 36\ \mathrm{pc}^{-3}\ \mathrm{yr}^{-1}$ , which represents an improvement of one order of magnitude over the upper limit set by the Large High Altitude Air Shower Observatory (LHAASO). In addition, we propose an observation strategy optimized for detecting PBH bursts.

Comments:

6 pages, 3 figures

Abstract: 2504.15446
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Title:Are Kronberger 80 and/or Kronberger 82 regions PeVatron candidates for LHAASO J2108+5157?

Authors:Akash Gupta, Eduardo De La Fuente, Ram K. Yadav, Alicia Porras, Saurabh Sharma, Sei Kato, Daniel Tafoya, Miguel A. Trinidad, Alberto Nigoche-Netro, Harold E. Viveros, Kazumasa Kawata, Hiromasa Suzuki, Munehiro Ohnishi, Ivan Toledano-Juarez, Takashi Sako, Masato Takita

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High-energy gamma rays have been detected in the region of LHAASO~J2108+5157 by the Fermi--LAT, HAWC and LHAASO-KM2A observatories. Cygnus~OB2 in Cygnus--X has been confirmed as the first strong stellar cluster PeVatron in our Galaxy. Thus, the star--forming regions Kronberger~80 and Kronberger~82, located in the field of LHAASO~J2108+5157, are analyzed to evaluate their stellar population and potential as associated PeVatron candidates. A distance of 10~kpc is adopted for Kronberger~80, while $\sim$ 1.6~kpc is estimated for Kronberger~82. Based on stellar densities, we report that their cluster radii are 2.5 $\arcmin$ and 2.0 $\arcmin$ , while IR photometry reveals poor stellar content in massive O-type stars in both cases. From optical data, the estimation of cluster ages are 5--12.6~Myr and $\lesssim$ 5~Myr, respectively. We conclude that, in contrast to the stellar content of Cygnus~OB2, it is unlikely that Kronberger~80 and Kronberger~82 are PeVatrons associated with LHAASO~J2108+5157. The presence of a PeVatron in this region remains a mystery, but we confirm that the two Kronberger regions are star--forming regions undergoing formation rather than evolution.

Comments:

21 pages, 10 figures, 3 Tables. This document is a preprint accepted for publication in Publications of the Astronomical Society of Japan. This version is the postprint prior to official journal formating. DOI: https://doi.org/10.1093/pasj/psaf046

Abstract: 2504.15890
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Tracing the imprints of large-scale magnetized structure on $γ$ rays from GRB 221009A

Authors:Saikat Das, Soebur Razzaque, Nestor Mirabal, Nicola Omodei, Kohta Murase, Israel Martinez-Castellanos

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We search for possible GeV-TeV gamma-ray imprints of ultrahigh-energy (UHE; $\gtrsim 0.1$ EeV) cosmic ray (CR) acceleration in the large-scale structures surrounding the brightest gamma-ray burst (GRB) explosion, GRB 221009A. Using 1.25 years of post-event Fermi Large Area Telescope (LAT) data, we construct a 1 GeV - 1 TeV test-statistic (TS) map within 15 Mpc of the burst. We identify two peaks in the TS map with TS $\geq 9$ . The most significant peak, J1911.8+2044, exhibits gamma-ray emission in pre-burst LAT data. The other peak, J1913.2+1901, coincides with a 664.6 GeV photon recorded $\sim191.9$ days after the GRB trigger and located at about $0.75^{\circ}$ from the GRB localization. The per-photon 95% containment angle for the LAT is about $0.25^{\circ}$ in the 100 GeV - 1 TeV energy range. We explore two possible origins for the $\gamma$ -ray emission: (1) UHECRs from GRB 221009A propagating through a magnetized cosmological volume in its vicinity, and (2) UHE or very-high-energy (VHE; $\gtrsim 100$ GeV) $\gamma$ -ray emission from GRB 221009A, propagating in the same volume. In both cases, electromagnetic cascade emission is induced in the structured region embedding the burst. If any TS features are related to large-scale imprints induced by cosmic rays, it might be further evidence that GRB 221009A accelerated UHECRs. However, our results show that alternative scenarios without invoking UHECRs cannot be ruled out, and the observed high-energy photon could be unrelated to GRB 221009A.

Comments:

21 pages and 6 figures

Abstract: 2504.15342
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Title:No evidence for excess AGN activity in recently quenched massive galaxies at cosmic noon

Authors:Omar Almaini, Vivienne Wild, David Maltby, Elizabeth Taylor, Kate Rowlands, Thomas de Lisle, Katherine Alatalo, Jimi Harrold, Guillaume Hewitt, Pallavi Patil, Maya Skarbinski

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We present an analysis of AGN activity within recently quenched massive galaxies at cosmic noon ( $z\sim 2$ ), using deep Chandra X-ray observations of the Ultra-Deep Survey (UDS) field. Our sample includes over 4000 massive galaxies ( $M_\ast > 10^{10.5}$ M $_{\odot}$ ) in the redshift range $1 < z < 3$ , including more than 200 transitionary post-starburst (PSB) systems. We find that X-ray emitting AGN are detected in $6.2 \pm 1.5$ per cent of massive PSBs at these redshifts, a detection rate that lies between those of star-forming and passive galaxies ( $8.2 \pm 0.5$ per cent and $5.7 \pm 0.8$ per cent, respectively). A stacking analysis shows that the average X-ray luminosity for PSBs is comparable to older passive galaxies, but a factor of $2.6 \pm 0.3$ below star-forming galaxies of similar redshift and stellar mass. The average X-ray luminosity in all populations appears to trace the star-formation rate, with PSBs showing low levels of AGN activity consistent with their reduced levels of star formation. We conclude that, on average, we see no evidence for excess AGN activity in the post-starburst phase. However, the low levels of AGN activity can be reconciled with the high-velocity outflows observed in many PSBs, assuming the rare X-ray detections represent short-lived bursts of black hole activity, visible $\sim$ 5 per cent of the time. Thus, X-ray AGN may help to maintain quiescence in massive galaxies at cosmic noon, but the evidence for a direct link to the primary quenching event remains elusive.

Comments:

15 pages, 24 figures. Accepted for publication in MNRAS

Abstract: 2504.15638
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Title:A characteristic optical variability time scale in jetted active galactic nuclei: a large gamma-ray emission sample

Authors:Dingrong Xiong, Mouyuan Sun, Jun-Xian Wang, Junhui Fan, Yongquan Xue, Minfeng Gu, Liang Chen, Yongyun Chen, Nan Ding, Fei Guo, Jirong Mao, Guowei Ren, Rui Xue, Dahai Yan, Shenbang Yang, Haiyun Zhang, Jinming Bai

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The variability mechanisms from jetted AGNs are still under debate. Here the damped random walk (DRW) model, implemented through Gaussian Processe (GPs), is used to fit the $ZTF$ long-term optical light curves of 1684 $\gamma$ -ray emission jetted AGNs. This analysis yields one of the largest samples with characteristic optical variability timescales for jetted AGNs. A single DRW model from GPs can fit the optical light curve of most jetted AGNs well/potentially well, while there are still some jetted AGNs whose light curve can not be fitted well by a single DRW model. After the jet power, proxied by gamma-ray luminosity, is introduced as a new parameter, new relationships among intrinsic variability time scales, black hole mass and jet power are discovered for efficient accretion AGNs ( $\tau^{\rm in} \propto M_{\rm BH}^{0.29^{+0.06}_{-0.06}}P_{\rm jet}^{-0.3^{+0.03}_{-0.03}}$ with scatter of approximately 0.09~dex) and for inefficient accretion AGNs ( $\tau^{\rm in} \propto M_{\rm BH}^{0.06^{+0.07}_{-0.07}}P_{\rm jet}^{0.37^{+0.11}_{-0.11}}$ with scatter of approximately 0.14~dex), respectively. Our results support that the optical variability of jetted AGNs with efficient accretion may originate within the standard accretion disk at UV emitting radii similar to non-jetted AGNs, and is directly related to the acceleration of shock in the jet and then enhanced through the beaming effect in beamed AGNs. For the jetted AGNs with inefficient accretion, the intrinsic timescale is consistent with the escape timescale of electrons.

Comments:

23 pages, 14 figures, 3 tables, Resubmitted to ApJS following second referee report

Abstract: 2504.15959
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Title:A Novel Relationship Between Gamma Ray Burst Duration And Photospheric Radius

Authors:Ranadeep Ghosh Dastidar, Paul Duffell

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Long Gamma Ray Bursts (lGRBs) are associated with jets in Type Ic broadline supernovae. The Collapsar model provides a theoretical framework for the jet formation from the core collapse of a massive star in such supernovae. The GRB can only be produced after a successful jet break out from the star. Under this formalism the GRB duration ( $t_{\rm{90}}$ ) has been hypothesized to be the difference between the central engine activity duration ( $t_{\rm{eng}}$ ) and the jet breakout time ( $t_{\rm{bo}}$ ), that is $t_{\rm{90}} = t_{\rm{eng}} - t_{\rm{bo}}$ . This disallows $t_{\rm{90}} > t_{\rm{eng}}$ and puts a lower bound on successful lGRB jet central engine duration ( $t_{\rm{eng}} > t_{\rm{bo}}$ ), various numerical simulations have shown otherwise. This study considers a photospheric GRB emission from a relativistic jet punching out of a Wolf-Rayet-like star. We use the bolometric lightcurve generated to calculate the lGRB duration ( $t_{\rm{90}}$ ) for varying engine duration. We find for longer engine duration the lGRB lightcurve reflects the jet profile and $t_{\rm{90}} \approx t_{\rm{eng}}$ . While for shorter engine duration, the $t_{\rm{90}}$ has photospheric radius ( $R_{\rm{ph}}$ ) dependence. This can be modeled by a relation, $t_{\rm{90}} = t^{\rm{90}}_{\rm{eng}} + 0.03\left(\frac{R_{\rm{ph}}}{c}\right)$ , where c is the speed of light, with a lower bound on $t_{\rm{90}}$ for a successful lGRB. This relation should be most relevant for possible low-luminous lGRBs originating from a collapsar with central engine duration comparable to the jet breakout time.

Comments:

10 pages, 8 plots

Abstract: 2504.16457
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Title:Scattering of stellar-mass black holes and gravitational wave bremsstrahlung radiation in AGN disks

Authors:Peter Lott, Christian Faulhaber, Joshua Brandt, Gongjie Li, Hareesh Bhaskar, Laura Cadonati

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Dynamics of stellar mass black holes (sBHs) embedded in active galactic nuclei (AGNs) could produce highly eccentric orbits near the central supermassive black hole, leading to repeated close encounters that emit gravitational waves in the LIGO frequency band. Many works have focused on the mergers of sBH in the disk that produce gravitational waves; however, sBHs in hyperbolic orbits also emit gravitational-wave \bremss{} that can be detected by ground-based interferometers like LIGO. In this work, we analyze the scattering of sBHs in an AGN disk as they migrate inside the disk, focusing on gravitational-wave \bremss{} emission. We determine how the gravitational-wave emission depends on the different parameters of the scattering experiments, such as the mass of the supermassive black hole and the sBH migration rate and mass ratio. We find that scattering with detectable gravitational-wave \bremss{} is more frequent around lower mass SMBHs ( $\sim 10^{5-6}$ M $_\odot$ ). We then conduct a suite of Monte Carlo simulations and estimated the rate for ground-based gravitational-wave detections to be in the range of 0.08 - 1194 $\text{Gpc}^{-3} \text{ yr}^{-1}$ , depending on migration forces and detection thresholds, with large uncertainties accounting for variations in possible AGN environments. The expected rate for our {\tt Fiducial} parameters is 3.2 $\text{Gpc}^{-3} \text{ yr}^{-1}$ . Finally, we provide first-principle gravitational wave templates produced by the encounters.

Comments:

This paper has been accepted for publication by the Astrophysical Journal

Abstract: 2504.17246
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Title:A Sandwich Model for Changing-Look AGNs

Authors:Qian-Qi Ma, Wei-Min Gu, Zhen-Yi Cai, Xinwu Cao, Jun-Xian Wang, Zhi-Xiang Zhang, Mouyuan Sun

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Abstract:The spectral variability of changing-look active galactic nuclei (CL-AGNs) occurred on timescales of years to tens of years, posing a significant challenge to the standard thin disk model. In this work, we propose a sandwich model, including an optically thick disk in the mid-plane (Disk 1) and two disks of low effective optical depth on both sides (Disk 2). These two types of disks are coupled with magnetic fields, which allow viscous torque interaction between them. As a consequence, the radial velocity of Disk 1 can increase by up to three orders of magnitude compared to the standard thin disk, leading to an equivalent decrease in the accretion timescale. Therefore, such a sandwich model can account for the rapid variability in CL-AGNs. In addition, we also discuss the influence of the magnetic pressure on Disk 2. When Disk 2 is dominated by the magnetic pressure, it resembles a "warm corona", which is responsible for the soft X-ray excess.

Comments:

10 pages, 4 figures, accepted for publication in ApJ

Abstract: 2504.16873
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Title:A LOFAR-style reconstruction of cosmic-ray air showers with SKA-Low

Authors:A. Corstanje, S. Buitink, S. Bouma, M. Desmet, J.R. Hörandel, T. Huege, P. Laub, K. Mulrey, A. Nelles, O. Scholten, K. Terveer, S. Thoudam, K. Watanabe

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Cosmic-ray air shower detection with the low-frequency part of the Square Kilometre Array (SKA) radio telescope is envisioned to yield very high precision measurements of the particle composition of cosmic rays between $10^{16}$ and $10^{18}$ eV. This is made possible by the extreme antenna density of the core of SKA-Low, surpassing the current most dense radio air shower observatory LOFAR by over an order of magnitude. In order to make these measurements, the technical implementation of this observation mode and the development of reconstruction methods have to happen hand-in-hand. As a first lower limit of what is obtainable, we apply the current most precise reconstruction methods as used at LOFAR to a first complete simulation of air shower signals for the SKA-Low array. We describe this simulation setup and discuss the obtainable accuracy and resolution. A special focus is put on effects of the dynamic range of the system, beamforming methods to lower the energy threshold, as well as the limits to the mass composition accuracy given by statistical and systematic uncertainties.

Comments:

14 pages, 10 figures. Submitted for publication in Phys. Rev. D

Abstract: 2504.17631
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Title:Modular Cosmic Ray Detector (MCORD) and its Potential Use in Various Physics Experiments, Astrophysics and Geophysics

Authors:M. Bielewicz, M. Kiecana, A. Bancer, J. Grzyb, L. Swiderski, M. Grodzicka-Kobylka, T. Szczesniak, A. Dziedzic, K. Grodzicki, E. Jaworska, A. Syntfeld-Kazuch

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Abstract:As part of the collaboration building a set of detectors for the new collider, our group was tasked with designing and building a large-scale cosmic ray detector, which was to complement the capabilities of the MPD (Dubna) detec-tor set. The detector was planned as a trigger for cosmic ray particles and to be used to calibrate and test other systems. Additional functions were to be the detection of pairs of high-energy muons originating from some parti-cle decay processes generated during collisions and con-tinuous observation of the cosmic muon stream in order to detect multi muons events. From the very beginning, the detector was designed as a scalable and universal device for many applications. The following work will present the basic features and parameters of the Modular COsmic Ray Detector (MCORD) and examples of its possible use in high energy physics, astrophysics and geology. Thanks to its universal nature, MCORD can be potential used as a fast trigger, neutron veto detector, muon detector and as a tool in muon tomography.

Comments:

The publication, based on the conference presentation (FEL2024-Warsaw), will be published on the Joint Accelerator Conferences Website (JACoW)

Abstract: 2504.15262
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Title:Revealing the 3D Cosmic Web through Gravitationally Constrained Neural Fields

Authors:Brandon Zhao, Aviad Levis, Liam Connor, Pratul P. Srinivasan, Katherine L. Bouman

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Abstract:Weak gravitational lensing is the slight distortion of galaxy shapes caused primarily by the gravitational effects of dark matter in the universe. In our work, we seek to invert the weak lensing signal from 2D telescope images to reconstruct a 3D map of the universe's dark matter field. While inversion typically yields a 2D projection of the dark matter field, accurate 3D maps of the dark matter distribution are essential for localizing structures of interest and testing theories of our universe. However, 3D inversion poses significant challenges. First, unlike standard 3D reconstruction that relies on multiple viewpoints, in this case, images are only observed from a single viewpoint. This challenge can be partially addressed by observing how galaxy emitters throughout the volume are lensed. However, this leads to the second challenge: the shapes and exact locations of unlensed galaxies are unknown, and can only be estimated with a very large degree of uncertainty. This introduces an overwhelming amount of noise which nearly drowns out the lensing signal completely. Previous approaches tackle this by imposing strong assumptions about the structures in the volume. We instead propose a methodology using a gravitationally-constrained neural field to flexibly model the continuous matter distribution. We take an analysis-by-synthesis approach, optimizing the weights of the neural network through a fully differentiable physical forward model to reproduce the lensing signal present in image measurements. We showcase our method on simulations, including realistic simulated measurements of dark matter distributions that mimic data from upcoming telescope surveys. Our results show that our method can not only outperform previous methods, but importantly is also able to recover potentially surprising dark matter structures.

Abstract: 2504.15340
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Cosmology in Extended Parameter Space with DESI DR2 BAO: A 2 $σ$ + Detection of Non-zero Neutrino Masses with an Update on Dynamical Dark Energy and Lensing Anomaly

Authors:Shouvik Roy Choudhury

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We obtain constraints in a 12 parameter cosmological model using the recent DESI Data Release (DR) 2 Baryon Acoustic Oscillations (BAO) data, combined with Cosmic Microwave Background (CMB) power spectra (Planck Public Release (PR) 4) and lensing (Planck PR4 + Atacama Cosmology Telescope (ACT) Data Release (DR) 6) data, uncalibrated type Ia Supernovae (SNe) data from Pantheon+ and Dark Energy Survey (DES) Year 5 (DESY5) samples, and Weak Lensing (WL: DES Year 1) data. The cosmological model consists of six $\Lambda$ CDM parameters, and additionally, the dynamical dark energy parameters ( $w_0$ , $w_a$ ), the sum of neutrino masses ( $\sum m_{\nu}$ ), the effective number of non-photon radiation species ( $N_{\textrm{eff}}$ ), the scaling of the lensing amplitude ( $A_{\textrm{lens}}$ ), and the running of the scalar spectral index ( $\alpha_s$ ). Our major findings are the following: i) With CMB+BAO+DESY5+WL, we obtain the first 2 $\sigma$ + detection of a non-zero $\sum m_{\nu} = 0.19^{+0.15}_{-0.18}$ eV (95%). Replacing DESY5 with Pantheon+ still yields a $\sim$ 1.9 $\sigma$ detection. ii) The cosmological constant lies at the edge of the 95% contour with CMB+BAO+Pantheon+, but is excluded at 2 $\sigma$ + with DESY5, leaving evidence for dynamical dark energy inconclusive, contrary to claims by DESI collaboration. iii) With CMB+BAO+SNe+WL, $A_{\textrm{lens}} = 1$ is excluded at $>2\sigma$ , while it remains consistent with unity without WL data - suggesting for the first time that the existence of lensing anomaly may depend on non-CMB datasets. iv) The Hubble tension persists at 3.6-4.2 $\sigma$ with CMB+BAO+SNe; WL data has minimal impact.

Comments:

15 pages, 6 figures, V2 has minor typos corrected and references updated

Abstract: 2504.17741
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Title:Multi-messenger standard-siren cosmology for third-generation gravitational-wave detectors: Considering observations of gamma-ray bursts and kilonovae

Authors:Tao Han, Jing-Fei Zhang, Xin Zhang

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In the third-generation (3G) gravitational-wave (GW) detector era, GW multi-messenger observations for binary neutron star merger events can exert great impacts on exploring the cosmic expansion history. Extending the previous work, we explore the potential of 3G GW standard siren observations in cosmological parameter estimation by considering their associated electromagnetic (EM) counterparts, including $\gamma$ -ray burst (GRB) coincidence observations by the Gravitational wave high-energy Electromagnetic Counterpart All-sky Monitor and GW-triggered target-of-opportunity observations of kilonovae by different optical survey projects. During an assumed 10-year observation, we predict that the number of detectable GW-kilonova events is $\sim 4900$ with redshifts below $\sim 0.4$ under GW network and Large Synoptic Survey Telescope in the $i$ band, which is three times more than that of GW-GRB detections. For the cosmological analysis, we find that with the inclusion of GW-kilonova detections, the constraints on cosmological parameters from GW-EM detections are significantly improved compared to those from GW-GRB detections. In particular, GW-EM detections can tightly constrain the Hubble constant with a precision ranging from $0.076\%$ to $0.034\%$ . Moreover, GW multi-messenger observations could effectively break the cosmological parameter degeneracies generated by the mainstream EM observations, CMB+BAO+SN (CBS). The combination of CBS and GW-EM can tightly constrain the equation of state parameters of dark energy $w$ in the $w$ CDM model and $w_0$ in the $w_0w_a$ CDM model with precisions of $0.72\%$ and $0.99\%$ , respectively, meeting the standard of precision cosmology. In conclusion, GW multi-messenger observations could play a crucial role in helping solve the Hubble tension and probing the fundamental nature of dark energy.

Comments:

21 pages, 14 figures

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For previous lists of abstracts of interest click Previous abstracts of interest

Title:Fermi-LAT and FAST observation of the gamma-ray binary HESS J0632+057

Title:An extremely soft and weak fast X-ray transient associated with a luminous supernova

Title:Hunting Star-Forming Galaxies in the Gamma-Ray Domain

Title:Prospective sensitivity of CTA on detection of evaporating primordial black holes

Title:Are Kronberger 80 and/or Kronberger 82 regions PeVatron candidates for LHAASO J2108+5157?

Title:Tracing the imprints of large-scale magnetized structure on γγ rays from GRB 221009A

Title:No evidence for excess AGN activity in recently quenched massive galaxies at cosmic noon

Title:A characteristic optical variability time scale in jetted active galactic nuclei: a large gamma-ray emission sample

Title:A Novel Relationship Between Gamma Ray Burst Duration And Photospheric Radius

Title:Scattering of stellar-mass black holes and gravitational wave bremsstrahlung radiation in AGN disks

Title:A Sandwich Model for Changing-Look AGNs

Title:A LOFAR-style reconstruction of cosmic-ray air showers with SKA-Low

Title:Modular Cosmic Ray Detector (MCORD) and its Potential Use in Various Physics Experiments, Astrophysics and Geophysics

Title:Revealing the 3D Cosmic Web through Gravitationally Constrained Neural Fields

Title:Cosmology in Extended Parameter Space with DESI DR2 BAO: A 2σσ+ Detection of Non-zero Neutrino Masses with an Update on Dynamical Dark Energy and Lensing Anomaly

Title:Multi-messenger standard-siren cosmology for third-generation gravitational-wave detectors: Considering observations of gamma-ray bursts and kilonovae

Tracing the imprints of large-scale magnetized structure on $γ$ rays from GRB 221009A

Cosmology in Extended Parameter Space with DESI DR2 BAO: A 2 $σ$ + Detection of Non-zero Neutrino Masses with an Update on Dynamical Dark Energy and Lensing Anomaly