Current date: 2026-01-05
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Datestamp limit: 2026-01-05 (0 days ago)
Created/updated limit: 2025-12-29 (7 days ago)
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Suggested sets: physics, physics:astro-ph, physics:gr-qc, physics:physics
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Scoring abstracts
Number of records retrieved: 538
Keyword score statistics
score 16 -- 1 abstracts
score 10 -- 1 abstracts
score 6 -- 3 abstracts
score 5 -- 2 abstracts
score 4 -- 4 abstracts
score 3 -- 6 abstracts
score 2 -- 11 abstracts
in total -- 28 abstracts
Articles that appeared on 2026-01-05
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[abstract 1 / 28] Wow! (score: 16)
- Title: Ring Asymmetry and Spin in M87*Authors: Vadim Bernshteyn, Nicholas S. Conroy, Michi Bauböck, Paul Tiede, Abhishek V. Joshi, Ben S. Prather, Charles F. Gammie, the Event Horizon Telescope Collaboration, :, Kazunori Akiyama, Ezequiel Albentosa-Ruíz, Antxon Alberdi, Walter Alef, Juan Carlos Algaba, Richard Anantua, Keiichi Asada, Rebecca Azulay, Anne-Kathrin Baczko, David Ball, Bidisha Bandyopadhyay, John Barrett, Bradford A. Benson, Dan Bintley, Lindy Blackburn, Raymond Blundell, Katherine L. Bouman, Geoffrey C. Bower, Michael Bremer, Roger Brissenden, Silke Britzen, Avery E. Broderick, Dominique Broguiere, Thomas Bronzwaer, Sandra Bustamante, Douglas F. Carlos, John E. Carlstrom, Andrew Chael, Chi-kwan Chan, Dominic O. Chang, Koushik Chatterjee, Ming-Tang Chen, Yongjun Chen, Xiaopeng Cheng, Paul Chichura, Ilje Cho, John E. Conway, Thomas M. Crawford, Geoffrey B. Crew, Alejandro Cruz-Osorio, Yuzhu Cui, Brandon Curd, Rohan Dahale, Jordy Davelaar, Mariafelicia De Laurentis, Roger Deane, Jason Dexter, Vedant Dhruv, Indu K. Dihingia, Sheperd S. Doeleman, Sergio A. Dzib, Razieh Emami, Heino Falcke, Joseph Farah, Vincent L. Fish, Edward Fomalont, H. Alyson Ford, Marianna Foschi, Raquel Fraga-Encinas, William T. Freeman, Per Friberg, Christian M. Fromm, Antonio Fuentes, Peter Galison, Roberto García, Olivier Gentaz, Boris Georgiev, Ciriaco Goddi, Roman Gold, Arturo I. Gómez-Ruiz, José L. Gómez, Minfeng Gu, Mark Gurwell, Kazuhiro Hada, Daryl Haggard, Ronald Hesper, Dirk Heumann, Luis C. Ho, Paul Ho, Mareki Honma, Chih-Wei L. Huang, Lei Huang, David H. Hughes, Shiro Ikeda, C. M. Violette Impellizzeri, Makoto Inoue, Sara Issaoun, David J. James, Buell T. Jannuzi, Michael Janssen, Britton Jeter, Wu Jiang, Alejandra Jiménez-Rosales, Michael D. Johnson, Svetlana Jorstad, Adam C. Jones, Taehyun Jung, Tomohisa Kawashima, Garrett K. Keating, Mark Kettenis, Dong-Jin Kim, Jae-Young Kim, Jongsoo Kim, Junhan Kim, Motoki Kino, Jun Yi Koay, Prashant Kocherlakota, Yutaro Kofuji, Patrick M. Koch, Shoko Koyama, Carsten Kramer, Joana A. Kramer, Michael Kramer, Thomas P. Krichbaum, Cheng-Yu Kuo, Noemi La Bella, Deokhyeong Lee, Sang-Sung Lee, Aviad Levis, Shaoliang Li, Zhiyuan Li, Rocco Lico, Greg Lindahl, Michael Lindqvist, Mikhail Lisakov, Jun Liu, Kuo Liu, Elisabetta Liuzzo, Wen-Ping Lo, Andrei P. Lobanov, Laurent Loinard, Colin J. Lonsdale, Amy E. Lowitz, Ru-Sen Lu, Nicholas R. MacDonald, Jirong Mao, Nicola Marchili, Sera Markoff, Daniel P. Marrone, Alan P. Marscher, Iván Martí-Vidal, Satoki Matsushita, Lynn D. Matthews, Lia Medeiros, Karl M. Menten, Hugo Messias, Izumi Mizuno, Yosuke Mizuno, Joshua Montgomery, Kotaro Moriyama, Monika Moscibrodzka, Wanga Mulaudzi, Cornelia Müller, Hendrik Müller, Alejandro Mus, Gibwa Musoke, Ioannis Myserlis, Hiroshi Nagai, Neil M. Nagar, Dhanya G. Nair, Masanori Nakamura, Gopal Narayanan, Iniyan Natarajan, Antonios Nathanail, Santiago Navarro Fuentes, Joey Neilsen, Chunchong Ni, Michael A. Nowak, Hiroki Okino, Héctor Raúl Olivares Sánchez, Feryal Özel, Daniel C. M. Palumbo, Georgios Filippos Paraschos, Jongho Park, Harriet Parsons, Nimesh Patel, Ue-Li Pen, Dominic W. Pesce, Vincent Piétu, Alexander Plavin, Aleksandar PopStefanija, Oliver Porth, Giacomo Principe, Dimitrios Psaltis, Hung-Yi Pu, Alexandra Rahlin, Venkatessh Ramakrishnan, Ramprasad Rao, Mark G. Rawlings, Luciano Rezzolla, Angelo Ricarte, Luca Ricci, Bart Ripperda, Jan Röder, Freek Roelofs, Cristina Romero-Cañizales, Eduardo Ros, Arash Roshanineshat, Helge Rottmann, Alan L. Roy, Ignacio Ruiz, Chet Ruszczyk, Kazi L. J. Rygl, León D. S. Salas, Salvador Sánchez, David Sánchez-Argüelles, Miguel Sánchez-Portal, Mahito Sasada, Kaushik Satapathy, Saurabh, Tuomas Savolainen, Karl-Friedrich Schuster, Zhiqiang Shen, Sasikumar Silpa, Randall Smith, Bong Won Sohn, Jason SooHoo, Kamal Souccar, Joshua S. Stanway, He Sun, Alexandra J. Tetarenko, Remo P. J. Tilanus, Michael Titus, Kenji Toma, Pablo Torne, Teresa Toscano, Efthalia Traianou, Sascha Trippe, Matthew Turk, Ilse van Bemmel, Huib Jan van Langevelde, Daniel R. van Rossum, Sebastiano D. von Fellenberg, Jesse Vos, Jan Wagner, Derek Ward-Thompson, John Wardle, Jasmin E. Washington, Jonathan Weintroub, Maciek Wielgus, Kaj Wiik, Michael F. Wondrak, George N. Wong, Jompoj Wongphexhauxsorn, Qingwen Wu, Paul Yamaguchi, Aristomenis Yfantis, Doosoo Yoon, André Young, Ziri Younsi, Wei Yu, Feng Yuan, Ye-Fei Yuan, Ai-Ling Zeng, J. Anton Zensus, Shuo Zhang, Guang-Yao Zhao,Comments: Accepted by ApJSubjects: astro-ph.HECreated: 2026-01-01; Updated: 2026-01-05; Datestamp: 2026-01-05
Event Horizon Telescope (EHT) images of the supermassive BLACK HOLE M87* depict an asymmetric ring of emission. General RELATIVISTIC MAGNETohydrodynamic (GRMHD) models of M87* and its accretion disk predict that the amplitude and location of the ring's peak brightness asymmetry should fluctuate due to turbulence in the source plasma. We compare the observed distribution of brightness asymmetry amplitudes to the simulated distribution in GRMHD models, across varying BLACK HOLE spin $a_{*}$. We show that, for strongly MAGNETized (MAD) models, three epochs of EHT data marginally disfavor $|a_{*}| \lesssim 0.2$. This is consistent with the Blandford-Znajek model for M87's JET, which predicts that M87* should have nonzero spin. We show quantitatively how future observations could improve spin constraints, and discuss how improved spin constraints could distinguish between differing JET-launching mechanisms and BLACK HOLE growth scenarios.
[abstract 2 / 28] Wow! (score: 10) - Title: The propagation of long GRB JETs through and beyond its progenitor starAuthors: Gerardo Urrutia, Agnieszka Janiuk,Comments: 8 pages, 2 figures, conference proceedingSubjects: astro-ph.HECreated: 2025-12-31; Updated: 2026-01-05; Datestamp: 2026-01-05
Long GAMMA-RAY BURSTs (lGRB) are produced by RELATIVISTIC JETs arising from the collapse of massive stars. Such progenitor environments present complex physical conditions that are challenging to model by numerical simulations. The difficulty increases when solving the accretion process and propagation of the outflows, as it requires covering distances from the BLACK HOLE horizon to beyond the progenitor star. General Relativistic Magnetohydrodynamic (GRMHD) simulations provide a convenient framework to study high-luminosity JETs, where MAGNETic flux plays an important role in the process of JET launching from the central engine. To follow the propagation of the JET through and beyond its progenitor environment, we use multi-scale simulations (i.e., AMR-based). In this work, we report results of 2.5-dimensional GRMHD simulations of a lGRB progenitor. We present highly MAGNETized, weakly MAGNETized, and non-MAGNETized pre-collapse stars, and discuss the observational implications for lGRB JETs.
[abstract 3 / 28] Yes (score: 6) - Title: Setting limits on BLAZAR-boosted DARK MATTER with xenon-based detectorsAuthors: Erin Barillier, Laura Manenti, Knut Mora, Paolo Padovani, Isaac Sarnoff, Yongheng Xu, Bjorn Penning, Francesco Arneodo,Comments:Subjects: astro-ph.HE hep-ex physics.data-anCreated: 2026-01-01; Updated: 2026-01-05; Datestamp: 2026-01-05
Dual-phase xenon time projection chambers achieve optimal sensitivity for DARK MATTER in the 10 to 1000 GeV/c$^2$ mass range, but sub-GeV DARK MATTER particles lack sufficient energy to produce nuclear recoils above detection thresholds in these detectors. Blazar-boosted DARK MATTER offers a way to overcome this limitation. Relativistic JETs in ACTIVE GALACTIC NUCLEi can accelerate light DARK MATTER in their host-galaxy halos to energies that can leave detectable nuclear recoil signals in xenon-based detectors on Earth. We present the first BLAZAR-boosted DARK MATTER search that incorporates detector response modeling, using public data from XENON1T and LZ for the BLAZAR TXS 0506+056. We model DARK MATTER-proton scattering in the JET environment, covering the full process from JET acceleration through to detector response, and we explore how the host-galaxy DARK MATTER density profile impacts the analysis. We set model-dependent exclusion regions on the dark-matter-nucleon scattering cross section for m$_χ$ approximately 1 MeV DARK MATTER, between 5.8$\times 10^{-31}$ cm$^2$ and 6.3$\times 10^{-29}$cm$^2$ using XENON1T data, and between 9.9$\times 10^{-32}$ cm$^2$ and 2.5$\times 10^{-28}$ cm$^2$ from LZ effective field theory (EFT) DARK MATTER searches. Our results show that astrophysical uncertainties, especially those in the dark-matter distribution near the supermassive BLACK HOLE, are the main limitation of this search rather than detector effects. The limits are therefore model-dependent and should be seen as exploratory, highlighting both the potential and the present uncertainties of BLAZAR-boosted DARK MATTER as a probe of light DARK MATTER.
[abstract 4 / 28] Yes (score: 6) - Title: On the Ultra-Long Gamma-Ray Transient GRB 250702B/EP250702Authors: Jin-Peng Zhang, Chen-Wei Wang, Zheng-Hang Yu, Shao-Lin Xiong, Shu-Xu Yi, Jia-Cong Liu, Wang-Chen Xue, Wen-Jun Tan, Zi-Rui Zhang, Rahim Moradi, Hao-Xuan Guo, Chao Zheng, Yan-Qiu Zhang, Yue Wang, Sheng-Lun Xie, Peng Zhang, Yang-Zhao Ren, Cheng-Kui Li, Xiao-Bo Li, Ce Cai, Shuo Xiao, Li-Ming Song, Shuang-Nan Zhang,Comments: 16 pages, 6 figures. Originally submitted to ApJL on September 2, 2025. Accepted by ApJL on December 27, 2025. Comments welcome!Subjects: astro-ph.HECreated: 2026-01-01; Updated: 2026-01-05; Datestamp: 2026-01-05
GRB 250702B/EP250702a is an interesting long-duration gamma-ray transient whose nature is in debate. To obtain a full picture in gamma-ray band, we implement a comprehensive targeted search of burst emission in a wide window of 30 days jointly with Insight-HXMT, GECAM and FERMI/GBM data within the ETJASMIN framework. In gamma-ray band, we find there is a 50-second precursor about 25 hours before the 4-hour main burst, which generally consists of 4 emission episodes. Remarkably, we find that the soft X-ray emission (after the main burst) decays as a power-law with start time aligning with the last episode of main emission and index of -5/3 perfectly consistent with the canonical prediction of fallback accretion. We conclude that the properties of precursor, main burst and the following soft X-ray emission strongly support the atypical collapsar Ultra-Long Gamma-Ray Burst (ULGRB) scenario rather than the Tidal Disruption Event (TDE), and all these gamma-ray and soft X-ray emission probably originate from RELATIVISTIC JET whose luminosity is dominated by the fallback accretion rate during the death collapse of a supergiant star.
[abstract 5 / 28] Yes (score: 6) - Title: Spectral Shapes of Pair Annihilation Line Emission in Magnetar Giant FlaresAuthors: Tomoki Wada, Shigeo S. Kimura,Comments: 12 pages, 6 figures, accepted for publication in ApJLSubjects: astro-ph.HECreated: 2026-01-02; Updated: 2026-01-05; Datestamp: 2026-01-05
We investigate the gamma-ray spectrum in the MeV range arising from electron-positron pair annihilation in fireballs associated with MAGNETar giant flares (MGFs), motivated by the recent observation of a MeV gamma-ray line feature in a bright GAMMA-RAY BURST, GRB~221009A. We develop an analytic model of line emission, demonstrating that RELATIVISTIC beaming results in a broadened, power-law spectral feature with photon index -1. We then perform Monte Carlo radiative transfer simulations incorporating electron-positron pair production, annihilation, and Compton scattering. The dependence of the emergent spectrum on the baryon loading is also examined, showing that a baryon-poor fireball is more favorable for the detection of MeV gamma rays. We further assess the detectability of the line component. The simulation results indicate that a power-law MeV component from the initial spike of a Galactic MGFs could be observed with current instruments, such as FERMI/GBM, and will be well within the reach of upcoming MeV gamma-ray satellites, which are expected to detect O(100) photons from such events.
[abstract 6 / 28] Yes (score: 5) - Title: Factors Controlling the Statistics of Magnetic Reconnection in MHD TurbulenceAuthors: M. B. Khan, M. A. Shay, S. Oughton, W. H. Matthaeus, C. C. Haggerty, S. Adhikari, P. A. Cassak, S. Fordin, D. O'Donnell, Y. Yang, R. Bandyopadhyay, S. Roy,Comments: Accepted in Physical Review ESubjects: physics.plasm-ph physics.space-phCreated: 2025-12-31; Updated: 2026-01-05; Datestamp: 2026-01-05
We study the statistics of dynamical quantities associated with MAGNETic RECONNECTion events embedded in a sea of strong background MAGNETohydrodynamic (MHD) turbulence using direct numerical simulations. We focus on the relationship of the RECONNECTion properties to the statistics of global turbulent fields. For the first time, we show that the distribution in turbulence of RECONNECTion rates (determined by upstream fields) is strongly correlated with the magnitude of the global turbulent MAGNETic field at the correlation scale. The average RECONNECTion rates, and associated dissipation rates, during turbulence are thus much larger than predicted by using turbulent MAGNETic field fluctuation amplitudes at the dissipation or kinetic scales. Magnetic RECONNECTion may therefore be playing a major role in energy dissipation in astrophysical and heliospheric turbulence.
[abstract 7 / 28] Yes (score: 5) - Title: High-energy Emission from Turbulent Electron-ion Coronae of Accreting Black HolesAuthors: Daniel Groselj, Alexander Philippov, Andrei M. Beloborodov, Richard Mushotzky,Comments: submitted for publication; animation available at https://youtu.be/0W-b242WMhwSubjects: astro-ph.HE physics.plasm-phCreated: 2026-01-02; Updated: 2026-01-05; Datestamp: 2026-01-05
We develop a model of particle energization and emission from strongly turbulent black-hole coronae. Our local model is based on a set of 2D radiative particle-in-cell simulations with an electron-ion plasma composition, injection and diffusive escape of photons and charged particles, and self-consistent Compton scattering. We show that a radiatively compact turbulent corona generates extended nonthermal ion distributions, while producing X-ray spectra consistent with observations. As an example, we demonstrate excellent agreement with observed X-ray spectra of NGC 4151. The predicted emission spectra feature an MeV tail, which can be studied with future MeV-band instruments. The MeV tail is shaped by nonthermal electrons accelerated at turbulent current sheets. We also find that the corona regulates itself into a two-temperature state, with ions much hotter than electrons. The ions carry away roughly 60% to 70% of the dissipated power, and their energization is driven by a combination of shocks and RECONNECTing current sheets, embedded into the turbulent flow.
[abstract 8 / 28] Yes (score: 4) - Title: Photon Accelerator in Magnetized PlasmaAuthors: Sergei Bulanov, Stepan Bulanov, Timur Esirkepov, Gianluca Gregori, Gabriele Grittani, Brandon Russell, Alec Thomas, Petr Valenta,Comments: 32 pages, 8 figuresSubjects: physics.plasm-ph astro-ph.HECreated: 2026-01-02; Updated: 2026-01-05; Datestamp: 2026-01-05
Strong MAGNETic fields and plasmas are intrinsically linked in both terrestrial laboratory experiments and in space phenomena. One of the most profound consequences of that is the change in relationship between the frequency and the wave number of electroMAGNETic waves propagating in plasma in the presence of such MAGNETic fields when compared to the case without these fields. Furthermore, MAGNETic fields alter electroMAGNETic wave interaction with RELATIVISTIC plasma waves, resulting in different outcomes for particle and radiation generation. For a RELATIVISTIC plasma wave-based photon acceleration this leads to an increased frequency gain, and, thus, potentially to higher efficiency. The influence of a MAGNETic field leads to quantitative and qualitative change in the properties of photon acceleration, amplifying the increase in the electroMAGNETic wave frequency.
[abstract 9 / 28] Yes (score: 4) - Title: Mass-loaded MAGNETic explosions in the context of Magnetar Giant Flares and Fast Radio BurstsAuthors: Konstantinos N. Gourgouliatos,Comments: 11 pages, 8 figures, comments are welcomeSubjects: astro-ph.HE physics.plasm-phCreated: 2026-01-01; Updated: 2026-01-05; Datestamp: 2026-01-05
Magnetar flares are highly energetic and rare events where intense high-energy emission is released from strongly MAGNETised neutron stars. Fast radio bursts are short and intense pulses of coherent radio emission. Their large dispersion measures support an extragalactic origin. While their exact origin still remains elusive, a substantial number of models associates them with strong MAGNETic field and high-energy RELATIVISTIC plasma found in the vicinity of MAGNETars. There is growing evidence that some fast radio bursts are associated to flare-type events from MAGNETars. We aim to provide a set of configurations describing a RELATIVISTIC, spherical, mass-loaded, MAGNETic explosion. We proceed by solving the equations of RELATIVISTIC MAGNETohydrodynamics, for a system that expands while maintaining its internal equilibrium. We employ a semi-analytical approach for the solution of the equations of RELATIVISTIC MAGNETohydrodynamics. We assume self-similarity in time and radius, axial symmetry, and separation of variables. There exists a dichotomy of solutions that correspond to higher and lower density and thermal pressure compared to the external one. The ratio of the poloidal to toroidal field and the inclusion of pressure and mass density affect the expansion velocity. The classes of these solutions can be applied to MAGNETar giant flares and fast radio bursts. The ones corresponding to overdensities and higher pressure can be associated to MAGNETar flares, whereas the ones corresponding to underdensities can be relevant to fast radio bursts corresponding to MAGNETically dominated events with low mass loading.
[abstract 10 / 28] Yes (score: 4) - Title: Hadronic Origin of Sub-PeV Gamma-Ray Emission from LHAASO J0621+3755Authors: Sonali Sahoo, Ankan Roy, Kritika Yadav, Reetanjali Moharana,Comments: 8 pages, 5 figures, 1 tableSubjects: astro-ph.HECreated: 2026-01-02; Updated: 2026-01-05; Datestamp: 2026-01-05
Very High Energy (VHE) gamma rays are primarily estimated to arise from high-energy electroMAGNETic interactions in pulsars and their halo through electron inverse Compton (IC) scattering. Hadronic channels like neutral pion decay have also been proposed to produce TeV-PeV gamma rays from the Pulsar halo. The neutral pions are expected to be generated from COSMIC RAY (CR) protons interacting with the ambient/cloud. The recent observations of sub-PeV gamma rays from the halo of pulsar PSR J0622+3749 by the Large High Altitude Air Shower Observatory Kilometre-Square Array (LHAASO-KM2A) detector provide a platform to explore different channels of their production. Previous studies support consistency with the leptonic modeling of the halo, which attributes its origin to slow diffusion in the interstellar medium. In this work, we investigated the possibility of proton-proton channel as the origin of these photons. To explain the observed gamma rays with energy $\sim 4$ TeV by the High-Altitude Water Cherenkov (HAWC) telescope till 200 TeV by the LHAASO observatory, one requires the CR proton luminosity to be $η_p\sim 0.1$ of the pulsar PSR J0622+3749 spin-down luminosity. In this case, we have considered the protons propagating in a one-zone superdiffusion environment, specifically $α= 1$ in a cloud of gas density 1 per cm$^{3}$.
[abstract 11 / 28] Yes (score: 4) - Title: Eccentric Disks from Circumbinary RingsAuthors: Leonardo Betancourt, Andrew MacFadyen, Jonathan Zrake,Comments: 12 pages, 5 figuresSubjects: astro-ph.HE astro-ph.GACreated: 2026-01-02; Updated: 2026-01-05; Datestamp: 2026-01-05
We perform high-resolution, grid-based hydrodynamics simulations of finite gaseous circumbinary rings (CBRs) viscously spreading into disks around binaries. We find that all systems suppress accretion onto the binary when the gas is relatively cold. CBRs display weak variability above the binary orbital frequency $Ω_b$ and a dominant, robust spectral peak at $\sim0.1Ω_b$ (half the fiducial lump frequency of $\sim0.2Ω_b$). Smaller rings relax into disks with enhanced gas eccentricity up to $e\simeq 0.3$. We consider the possibility that inefficiently-accreting, intermediate-mass ($\sim10^4 M_\odot$) BLACK HOLE binaries may be sources of quasi-periodic eruptions when rejected streams shock the cavity wall and radiate in the UV or soft X-ray. We discuss the implications of eccentric disks evolved from CBRs for QUASAR light curves and asymmetric, time-variable double-peaked line emission from disks in galactic nuclei. If binaries drive asymmetry in accretion disk line profiles, our study suggests that the progenitor CBR must have been very compact.
[abstract 12 / 28] (score: 3) - Title: From "The Cliff" to "Virgil": Mapping the Spectral Diversity of Little Red Dots with JWST/NIRSpecAuthors: Guillermo Barro, Pablo G. Perez-Gonzalez, Dale Kocevski, Jonathan R. Trump, Mark Dickinson, Pablo Arrabal Haro, Madisyn Brooks, Callum T. Donnan, James S. Dunlop, Steven L. Finkelstein, Maximilien Franco, Giovanni Gandolfi, Mauro Giavalisco, Norman A. Grogin, Michaela Hirschmann, Jeyhan S. Kartaltepe, Anton M. Koekemoer, Rebecca L. Larson, Gene C. K. Leung, Ray A. Lucas, Elizabeth J. McGrath, Casey Papovich, Borja Perez-Diaz, Rachel S. Somerville, Elizabeth Taylor, Anthony J. Taylor, Roberta Tripodi, L. Y. Aaron Yung, Xin Wang,Comments: 26 pages, 13 figures, submitted to ApJ. Minor corrections have been made, and co-authors and an additional figure have been added following feedback on the first submissionSubjects: astro-ph.GACreated: 2026-01-01; Updated: 2026-01-05; Datestamp: 2026-01-05
One of JWST's most unexpected discoveries is the emergence of "Little Red Dots'' (LRDs): compact sources at $z \gtrsim 3$ with blue rest-frame UV continua, red optical slopes, and broad Balmer emission lines that challenge standard models and suggest a population of early, unusual ACTIVE GALACTIC NUCLEi (AGNs). Using a comprehensive photometric selection and public NIRSpec/PRISM spectroscopy across six JWST deep fields, we identify a large sample of 118 LRDs with high-S/N spectra, enabling a population-wide analysis of their UV-optical continuum and emission lines. We find clear correlations between rest-frame color ([0.3-0.9\,$μ$m]) and slopes: bluer LRDs have blue UV slopes ($β_{ν,\mathrm{UV}} \sim 0.3$) and red optical slopes, while redder LRDs exhibit redder UV slopes ($β_{ν,\mathrm{UV}} \sim 1.1$). The continuum shape shows a similar trend: redder LRDs display prominent Balmer breaks and curvature, while bluer LRDs follow power-law-like optical SEDs. From literature compilations, $\sim$60% of known broad-line AGNs satisfy our LRD criteria, and up to 90% of LRDs show broad Balmer lines. Emission-line diagnostics reveal a shift from high H$_α$/H$_β$ and low [OIII]$\lambda5007$/H$_β$ in redder LRDs to the opposite in bluer ones, along with stronger narrow-line equivalent widths, suggesting a transition from AGN- to host-dominated emission. We fit the spectra with a two-component model combining a gas-enshrouded BLACK HOLE (BH) and a galaxy host. Redder LRDs require higher-luminosity, unreddened BHs and modestly reddened hosts; bluer LRDs require lower-luminosity, reddened BHs and dust-free galaxies. This framework reproduces the diversity in colors and spectral shape by varying BH luminosity, obscuration, and host-to-BH luminosity ratio.
[abstract 13 / 28] (score: 3) - Title: A free-floating-planet microlensing event caused by a Saturn-mass objectAuthors: Subo Dong, Zexuan Wu, Yoon-Hyun Ryu, Andrzej Udalski, Przemek Mroz, Krzysztof A. Rybicki, Simon T. Hodgkin, Lukasz Wyrzykowski, Laurent Eyer, Thomas Bensby, Ping Chen, Sharon X. Wang, Andrew Gould, Hongjing Yang, Michael D. Albrow, Sun-Ju Chung, Cheongho Han, Kyu-Ha Hwang, Youn Kil Jung, In-Gu Shin, Yossi Shvartzvald, Jennifer C. Yee, Weicheng Zang, Dong-Jin Kim, Chung-Uk Lee, Byeong-Gon Park, Radoslaw Poleski, Jan Skowron, Michal K. Szymanski, Igor Soszynski, Pawel Pietrukowicz, Szymon Kozlowski, Dorota M. Skowron, Krzysztof Ulaczyk, Mariusz Gromadzki, Milena Ratajczak, Patryk Iwanek, Marcin Wrona, Mateusz J. Mroz, Guy Rixon, Diana L. Harrison, Elme Breedt,Comments: Published in Science. This is the authors' version. See the ancillary file for an animation associated with Fig. 2Subjects: astro-ph.EP astro-ph.GA astro-ph.SRCreated: 2025-12-31; Updated: 2026-01-05; Datestamp: 2026-01-05
A population of free-floating planets is known from gravitational microlensing surveys. None have a directly measured mass, owing to a degeneracy with the distance, but the population statistics indicate that many are less massive than Jupiter. We report a microlensing event -- KMT-2024-BLG-0792/OGLE-2024-BLG-0516, which was observed from both ground- and space-based telescopes -- that breaks the mass-distance degeneracy. The event was caused by an object with 0.219^{+0.075}_{-0.046} Jupiter masses that is either gravitationally unbound or on a very wide orbit. Through comparison with the statistical properties of other observed microlensing events and predictions from simulations, we infer that this object likely formed in a protoplanetary disk (like a planet), not in isolation (like a brown dwarf), and dynamical processes then ejected it from its birth place, producing a free-floating object.
[abstract 14 / 28] (score: 3) - Title: Little Red Dots: The Assembly of Early Supermassive Black Holes in the JWST EraAuthors: David D Vaida, Ryan Jeffrey Farber,Comments: Submitted to Frontiers in Astronomy & Space Sciences, 13 pages, 2 figuresSubjects: astro-ph.GA astro-ph.COCreated: 2025-12-31; Updated: 2026-01-05; Datestamp: 2026-01-05
Since the launch of James Webb Space Telescope (JWST) in late 2021, our understanding of high-redshift objects has faced several upheavals. JWST has discovered much more massive galaxies and supermassive BLACK HOLEs (SMBH) than cosmological models had expected. Furthermore, JWST observations have revealed an entirely novel population of high-redshift objects. Characterized by a dominant red rest-frame component and point-like morphology, these ``little red dots'' (LRD) have set off a flurry of observational and theoretical follow-up. The current identity of LRD is highly debated, yet falling into two main scenarios: ACTIVE GALACTIC NUCLEi (i.e., SMBH) or compact star-forming regions. If star-forming, LRD would represent the highest stellar densities ever observed. If SMBH, their high Eddington fractions, and already high masses, help elucidate the growth of the most massive SMBH found by JWST in the early Universe ($z \gtrsim4)$. In this mini-review, we present the observational evidence accumulated to date, including sub-millimeter probes of LRD dust masses, constraints on radio and X-ray emission from stacking, and rest-frame ultraviolet \& optical measurements provided by JWST. Furthermore, we highlight how identifying additional LRD that are truly primarily SMBH-driven may help to shed light on the formation of `overly massive' SMBH discovered by JWST within the first billion years since the Big Bang.
[abstract 15 / 28] (score: 3) - Title: Spectral performance of single-channel plastic and GAGG scintillator bars of the CUbesat Solar Polarimeter (CUSP)Authors: Nicolas De Angelis, Abhay Kumar, Sergio Fabiani, Ettore Del Monte, Enrico Costa, Giovanni Lombardi, Alda Rubini, Paolo Soffitta, Andrea Alimenti, Riccardo Campana, Mauro Centrone, Giovanni De Cesare, Sergio Di Cosimo, Giuseppe Di Persio, Alessandro Lacerenza, Pasqualino Loffredo, Gabriele Minervini, Fabio Muleri, Paolo Romano, Emanuele Scalise, Enrico Silva, Davide Albanesi, Ilaria Baffo, Daniele Brienza, Valerio Campomaggiore, Giovanni Cucinella, Andrea Curatolo, Giulia de Iulis, Andrea Del Re, Vito Di Bari, Simone Di Filippo, Immacolata Donnarumma, Pierluigi Fanelli, Nicolas Gagliardi, Paolo Leonetti, Matteo Mergè, Dario Modenini, Andrea Negri, Daniele Pecorella, Massimo Perelli, Alice Ponti, Francesca Sbop, Paolo Tortora, Alessandro Turchi, Valerio Vagelli, Emanuele Zaccagnino, Alessandro Zambardi, Costantino Zazza,Comments: Accepted in MDPI Particles, Advances in Space AstroParticle Physics: Frontier Technologies for Particle Measurements in Space, 2025 Edition; 17 pages, 15 figures, 2 tablesSubjects: astro-ph.IM astro-ph.SR physics.space-phCreated: 2026-01-01; Updated: 2026-01-05; Datestamp: 2026-01-05
Our Sun is the closest X-ray astrophysical source to Earth. As such, it makes a formidable case study to better understand astrophysical processes. Solar flares are in particular very interesting as they are linked to coronal mass ejections as well as MAGNETic field RECONNECTion sites in the solar atmosphere. Flares can therefore provide insightful information on the physical processes at play on their production sites, but also on the emission and acceleration of energetic charged particles towards our planet, making it a formidable forecasting tool for space weather. While solar flares are critical to understanding MAGNETic RECONNECTion and particle acceleration, their hard X-ray POLARIZATION -- key to distinguishing between competing theoretical models -- remains poorly constrained by existing observations. To address this, we present the CUbesat Solar Polarimeter (CUSP), a mission under development to perform solar flare polarimetry in the 25-100 keV energy range. CUSP consists of a 6U-XL platform hosting a dual-phase Compton polarimeter. The polarimeter is made of a central assembly of four 4x4 arrays of plastic scintillators, each coupled to multi-anode photomultiplier tubes, surrounded by four strips of eight elongated GAGG scintillator bars coupled to avalanche photodiodes. Both types of sensors from Hamamatsu are respectively read out by the MAROC-3A and SKIROC-2A ASICs from Weeroc. In this manuscript, we present the preliminary spectral performances of single plastic and GAGG channels measured in the laboratory using development boards of the ASICs foreseen for the flight model.
[abstract 16 / 28] (score: 3) - Title: Elaboration on the kinetic approach of Derbenev and Kondratenko to spin-polarized beams in electron storage ringsAuthors: Klaus Heinemann, Dan T. Abell, Jose Agudelo, Desmond P. Barber, Oleksii Beznosov, Joseph P. Devlin, James A. Ellison, Eiad Hamwi, Boaz Nash, Mathias Vogt,Comments:Subjects: physics.acc-phCreated: 2026-01-02; Updated: 2026-01-05; Datestamp: 2026-01-05
We present a detailed account of the kinetic approach for describing the effect of SYNCHROTRON radiation on electron and positron spin POLARIZATION in storage rings. This approach was introduced in 1974 by Derbenev and Kondratenko and was extended by us in 2019. The kinetic approach is much less frequently utilized but it is more general than the original non-kinetic approach of Derbenev and Kondratenko from 1972 since the kinetic approach is not centered on the invariant spin field. As with the non-kinetic approach the kinetic approach covers the radiative dePOLARIZATION effect, the Sokolov-Ternov effect and its Baier-Katkov correction as well as the kinetic POLARIZATION effect but it enables the calculation of corrections to the original Derbenev-Kondratenko formulas and thereby provides estimates of the reliability of the latter. It is applicable to storage rings with energies from a few GeV up to the energies of the FCC-ee and CEPC and beyond. The kinetic approach is based on the spin-orbit Wigner functions which lead to the so-called Bloch equation for the POLARIZATION density which is a generalization of Fokker-Planck equations to spin motion. In turn, as discovered in 2019, the Bloch equation is based on stochastic ordinary differential equations which can be used to develop Monte-Carlo spin-tracking codes covering the key effects beyond just radiative dePOLARIZATION.
[abstract 17 / 28] (score: 3) - Title: XRISM finds the Changing-Look AGN NGC 1365 in an extended low state: A dense, highly ionized outflow obscures the central sourceAuthors: Fatima Zaidouni, Erin Kara, Peter Kosec, Ehud Behar, Richard Mushotzky, Michael Koss, Anna Juráňová, Elias Kammoun, Laura W. Brenneman, Joheen Chakraborty, Ken Ebisawa, Megan E. Eckart, Andrew C. Fabian, Yasushi Fukazawa, Javier A. García, Liyi Gu, Megan Masterson, Shoji Ogawa, Takashi Okajima, Stéphane Paltani, Daniele Rogantini, Yuichi Terashima, Brian J. Williams, Satoshi Yamada,Comments:Subjects: astro-ph.HECreated: 2026-01-02; Updated: 2026-01-05; Datestamp: 2026-01-05
We present the first XRISM/Resolve observations of the ACTIVE GALACTIC NUCLEus, NGC 1365, obtained in 2024 February and July. NGC 1365 is known for rapid transitions between Compton-thick and Compton-thin states, along with strong absorption from a highly ionized wind. During our observations, the source is found in a persistent low-flux state, characterized by a decrease in hard-X-ray luminosity and significant line-of-sight obscuration. In this state, XRISM/Resolve reveals clear Fe\,\textsc{xxv} and Fe\,\textsc{xxvi} absorption lines together with, for the first time in this source, corresponding emission lines. These features may arise either from reemission from a photoionized wind (P Cygni profile) or from collisionally ionized gas associated with outflow-driven shocks in the interstellar medium. We estimate the wind launch radius to be approximately $10^{16}~\mathrm{cm}$ ($\sim 10^4 R_{\mathrm{g}}$), consistent with the location of the X-ray broad-line region. We also resolve a broadened Fe K$α$ line by $σ\sim 1300$ km s$^{-1}$ placing it at similar scales to the wind, consistent with radii inferred from disk-broadening models and the variability of the Fe K$α$ broad line. The similarity of the Fe K$α$ profile to the H$β$ wing and broad Pa$α$ width indicates that the X-ray-emitting region is likely cospatial with the optical/IR broad-line region and originates from the same gas.
[abstract 18 / 28] (score: 2) - Title: Euclidean teleparallel relativity and BLACK HOLE partition functionsAuthors: Jose Beltrán Jiménez, Tomi S. Koivisto,Comments: V2. Edited the note into a PRD Letter. The point is made sharperSubjects: gr-qcCreated: 2026-01-01; Updated: 2026-01-05; Datestamp: 2026-01-05
The Euclidean path integral approach to quantum gravity is conventionally formulated in terms of the Einstein-Hilbert-York-Gibbons-Hawking action, which requires suitable subtractions to produce the correct BLACK HOLE partition function. However, there is a unique, canonical teleparallel reformulation which reproduces the same results without subtractions or other ambiguities. This is verified in the case of a BLACK HOLE with or without an electric or a MAGNETic charge and in a background with or without a cosmological constant. Moreover, a new quasilocal prescription is proposed and tested, where the BLACK HOLE partition function is determined solely by the horizon boundary term, yielding the correct Helmholtz free energy without the need for counterterms.
[abstract 19 / 28] (score: 2) - Title: Vortex driven Schwingrer pair creation in the MAGNETosphere of SgrA*Authors: Zaza N. Osmanov,Comments: 7 pages, 1 figure1Subjects: astro-ph.HECreated: 2026-01-02; Updated: 2026-01-05; Datestamp: 2026-01-05
In this work, we explore the possibility of Schwinger pair creation triggered by MAGNETo-centrifugal effects in the MAGNETosphere of SgrA*. We show that these effects become extremely efficient in the presence of a vortex-driven MAGNETic field, whose strength exceeds previous estimates by several orders of magnitude. The dynamics of MAGNETo-centrifugally accelerated charged particles leads to charge separation, thereby parametrically exciting Langmuir waves. The associated electric field grows exponentially and upon reaching the Schwinger critical threshold, initiates efficient electron-positron pair production, which is ultimately saturated by annihilation processes.
[abstract 20 / 28] (score: 2) - Title: Accretion Flow Properties of MAXI J1834-021 During Its Double-Outbursts In 2023Authors: Dipak Debnath, Hsiang-Kuang Chang,Comments: 10 Pages, 7 Figures (In Journal Communication)Subjects: astro-ph.HECreated: 2026-01-01; Updated: 2026-01-05; Datestamp: 2026-01-05
The Galactic transient BLACK HOLE candidate MAXI J1834-021 exhibited `faint' outbursting activity for approximately $10$ months following its discovery on February 5, 2023. We study the evolution of both the temporal (hard and soft band photon count rates, hardness ratios, and QPO frequencies) and spectral properties of the source using NICER data between March 7 and October 4, 2023. The outburst profile and the nature of QPOs suggest that the source underwent a mini-outburst following the primary outburst. A monotonic evolution of low-frequency QPOs from higher to lower frequencies is observed during the primary outbursting phase. Both phenomenological (diskbb plus powerlaw) and physical (Two Component Advective Flow) model fitted spectral studies suggest that during the entire epoch, the source remained in harder spectral states, with a clear dominance of nonthermal emissions from the `hot' Compton cloud. Based on the evolution of the spectral and temporal properties, the 2023 outbursting activity of MAXI J1834-021 can be classified as a combination of double `failed' outbursts, as no softer spectral states were observed. The spectral analysis with the TCAF model also gives an estimate of the source mass as $12.3\pm0.2~M_\odot$.
[abstract 21 / 28] (score: 2) - Title: Properties of current sheets in two-dimensional tearing-mediated MAGNETohydrodynamic turbulenceAuthors: Chen Shi, Marco Velli, Nikos Sioulas, Zijin Zhang,Comments:Subjects: astro-ph.SR physics.space-phCreated: 2026-01-01; Updated: 2026-01-05; Datestamp: 2026-01-05
It is well known that the nonlinear evolution of MAGNETohydrodynamic (MHD) turbulence generates intermittent current sheets. In the solar wind turbulence, current sheets are frequently observed and they are believed to be an important pathway for the turbulence energy to dissipate and heat the plasma. In this study, we perform a comprehensive analysis of current sheets in a high-resolution two-dimensional simulation of balanced, incompressible MHD turbulence. The simulation parameters are selected such that tearing mode instability is triggered and plasmoids are generated throughout the simulation domain. We develop an automated method to identify current sheets and accurately quantify their key parameters including thickness ($a$), length ($L$), and Lundquist number ($S$). Before the triggering of tearing instability, the current sheet lengths are mostly comparable to the energy injection scale. After the tearing mode onsets, smaller current sheets with lower Lundquist numbers are generated. We find that the aspect ratio ($a/L$) of the current sheets scales approximately as $S^{-1/2}$, i.e. the Sweet-Parker scaling. While a power-law scaling between $L$ and $a$ is observed, no clear correlation is found between the upstream MAGNETic field strength and thickness $a$. Finally, although the turbulence energy shows anisotropy between the directions parallel and perpendicular to the local MAGNETic field increment, we do not observe a direct correspondence between the shape of the current sheets and that of the turbulence "eddies." These results suggest that one needs to be cautious when applying the scale-dependent dynamic alignment model to the analysis of current sheets in MHD turbulence.
[abstract 22 / 28] (score: 2) - Title: Multi-messenger detectability of continuous gravitational waves from the near future to next generation detectorsAuthors: Benjamin J. Owen, Binod Rajbhandari,Comments: 14 pages, 6 figuresSubjects: gr-qc astro-ph.HECreated: 2026-01-01; Updated: 2026-01-05; Datestamp: 2026-01-05
Continuous gravitational waves have the potential to transform gravitational wave astronomy and yield fresh insights into astrophysics, nuclear and particle physics, and condensed matter physics. We evaluate their detectability by combining various theoretical and observational arguments from the literature and systematically applying those arguments to known astronomical objects and future gravitational wave detectors. We detail and update previous estimates made in support of Cosmic Explorer [M. Evans et al., arXiv:2306.13745; I. Gupta et al., Class. Quantum Grav. 41, 245001 (2024)]. It is commonly argued that the spins of accreting neutron stars are regulated by gravitational wave emission and that millisecond pulsars contain a young pulsar's MAGNETic field buried under accreted material. If either of these arguments holds, the first detection of continuous gravitational waves is likely with near future upgrades of current detectors, and many detections are likely with next generation detectors such as Cosmic Explorer and the Einstein Telescope. A lack of detections in the next several years would begin to raise serious doubts about current theories of millisecond pulsar formation.
[abstract 23 / 28] (score: 2) - Title: Colloquium: Multimessenger astronomy with continuous gravitational waves and future detectorsAuthors: Benjamin J. Owen,Comments: 13 pages, 4 figures, to appear in Rev. Mod. PhysSubjects: gr-qc astro-ph.HECreated: 2026-01-02; Updated: 2026-01-05; Datestamp: 2026-01-05
Continuous gravitational waves from rapidly rotating neutron stars are on the new frontiers of gravitational wave astrophysics and have strong connections to electroMAGNETic astronomy, nuclear astrophysics, and condensed matter physics. In this Colloquium I survey prospects for detection of continuous gravitational waves from various neutron star populations, especially aided by electroMAGNETic observations. Although there are caveats, current theories and observations suggest that the first detections are likely within a few years, and that many are likely in the era of next generation detectors such as Cosmic Explorer and the Einstein Telescope. I also survey what can be learned from these signals, each one of which will contain more cycles than all the compact binary mergers ever detected. Since continuous gravitational wave emission mechanisms depend on aspects of neutron star physics, such as crustal elasticity, which are not well constrained by current astronomical observations and physical experiments, their detection can tell us a great deal that is new about extreme matter. Even more can be learned by combining gravitational wave observations with data from the Square Kilometre Array, the Next Generation Very Large Array, FAST, and other electroMAGNETic detectors operating in the next generation era.
[abstract 24 / 28] (score: 2) - Title: From Grounding to Stabilisation: Adequacy as a Criterion for Scientific ExplanationAuthors: Jonathon Sendall,Comments: 14 pagesSubjects: physics.hist-phCreated: 2026-01-01; Updated: 2026-01-05; Datestamp: 2026-01-05
This paper develops a process-based account of scientific explanation that reconceives grounding in terms of stabilisation. Grounding theories capture hierarchical dependence but lack criteria for when explanations remain adequate under model updates, perturbations, and theory change. Stabilisation is formally defined by a schema \(C \to P(I)\), where explanatory relations are sufficient when they preserve specified relational invariants under admissible transformations. This replaces the search for ultimate foundations with operational adequacy tests indexed to measurable invariance, resolving infinite regress worries while preserving a modest scientific realism. Applications show unifying power: theory change becomes an empirical question about structural continuity; quantum measurement becomes apparatus-dependent pattern selection; the effectiveness of mathematics reflects convergence on transformation-invariant descriptions; and emergence versus reduction reduces to stability of cross-level mappings. The BLACK HOLE event horizon illustrates how ontologically identical states can diverge in admissible evolution, revealing process as explanatorily fundamental. Companion work develops apparatus-dependent adequacy protocols, including pointer-basis rotation and coupling-spectra methods, turning the framework into a falsifiable research programme across quantum, thermodynamic, and RELATIVISTIC domains.
[abstract 25 / 28] (score: 2) - Title: KMT-2024-BLG-0816/OGLE-2024-BLG-0519 -- A Microlensing Event with Candidate Free-Floating Planet Lens and Blended LightAuthors: R. Poleski, Y. -H. Ryu, A. Udalski, W. Zang, M. D. Albrow, S. -J. Chung, A. Gould, C. Han, K. -H. Hwang, Y. K. Jung, I. -G. Shin, Y. Shvartzvald, J. C. Yee, H. Yang, D. -J. Kim, C. -U. Lee, B. -G. Park, M. K. Szymański, I. Soszyński, K. Ulaczyk, P. Pietrukowicz, J. Skowron, D. Skowron, P. Mróz, K. Rybicki, P. Iwanek, M. Wrona, M. Gromadzki, M. Mróz, M. Ratajczak,Comments: submitted; 18 pages, 6 figuresSubjects: astro-ph.EP astro-ph.GACreated: 2026-01-01; Updated: 2026-01-05; Datestamp: 2026-01-05
We present the discovery of a free-floating planet microlensing event KMT-2024-BLG-0816. The event shows finite-source effect, significant blending light, and no microlensing signal from a putative planet host. Among the free-floating planet events with finite source effects, this is the only event with unresolved blending light. We discuss how follow-up observations can be used to determine whether the blending light originates from a putative planet host.
[abstract 26 / 28] (score: 2) - Title: Asymmetric torus variability in ACTIVE GALACTIC NUCLEi driven by global brightening and dimmingAuthors: Suyeon Son, Minjin Kim, Luis C. Ho,Comments: Accepted for publication in A&ASubjects: astro-ph.GACreated: 2026-01-01; Updated: 2026-01-05; Datestamp: 2026-01-05
Temporal asymmetry in the flux variability of ACTIVE GALACTIC NUCLEi (AGNs) offers key insights into the physical mechanisms driving AGN variability. In this study, we investigated the variability of the torus by analyzing temporal asymmetry in the mid-infrared (MIR) continuum. We compared ensemble structure functions between the brightening and dimming phases for AGNs at $0.15
[abstract 27 / 28] (score: 2) - Title: Taxonomy of periodic orbits and gravitational waves in a deformed Schwarzschild BLACK HOLE spacetimeAuthors: Zhutong Hua, Zhen-Tao He, Jiageng Jiao, Jing-Qi Lai, Yu Tian,Comments: 17pages,8 figuresSubjects: gr-qc astro-ph.HECreated: 2026-01-02; Updated: 2026-01-05; Datestamp: 2026-01-05
In this paper, we investigate periodic orbits of test particles around a deformed Schwarzschild BLACK HOLE and the resulting gravitational waves. Firstly, we examine the properties of circular orbits and find that circular orbits could disappear when the deformation is large enough. Then, using an orbital taxonomy, we characterize various periodic orbits with a set of triples, which describes the zoom-whirl behaviours. We also calculate the gravitational waveform signals generated by different periodic orbits, revealing the influence of the deformation on the gravitational wave, which can be potentially picked up by future space-based detectors.
[abstract 28 / 28] (score: 2) - Title: Gravitational instability in partially ionized plasmas: A two-fluid approachAuthors: A. P. Misra, V. Krishan,Comments: 6 pages, 1 figureSubjects: physics.plasm-ph astro-ph.SRCreated: 2026-01-02; Updated: 2026-01-05; Datestamp: 2026-01-05
We propose a new two-fluid model for a partially ionized MAGNEToplasma under gravity, where electrons and neutrals are treated as a single fluid, and singly charged positive ions are a separate fluid. We observe that the classical result of gravitational instability (also known as Rayleigh-Taylor instability) in fully ionized plasmas is significantly modified by the influence of ion-neutral collisions (with frequency $ν_{\rm{in}}$) and transverse wave numbers ($k_x$ and $k_y$). The instability growth rate can be enhanced or decreased depending on the values of the ratios $κ\equiv k_x/k_y$ and $f\equivν_{\rm{in}}/Ω_{\rm{ci}}$, where $Ω_{\rm{ci}}$ is the ion-cyclotron frequency. We also estimate the growth rates relevant to the ionospheric E-region and solar atmosphere, noting that such growth rates can be maximized for $κ,~f\ll1$, or for $κ>1$ and $f\sim0.64$, and minimized for $f\gg1$ irrespective of the value of $κ$. Furthermore, the timescale of instability ranges from $1$ minute to $2$ minutes in the solar atmosphere, while in the E region, it ranges from $1$ minute to $80$ minutes. The latter can be a satisfactory result for the reported lifetime of solar prominence threads.
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