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20212026
most citedPolarized Blazar X-rays imply particle acceleration in shocks

140 citations · 172 across the 30 of their papers we have counts for

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27 papers · 1 filter

astro-ph.HE2026

A Search for GeV Emission from Magnetar Giant Flare Candidates with Fermi-LAT

Vikas Chand, Michela Negro, Nicola Omodei +5

The discovery of delayed GeV emission from the extragalactic magnetar giant flare (MGF) GRB 200415A, located in the nearby Sculptor galaxy, revealed for the first time that these r…

astro-ph.HE2026

Discriminating blazar emission models with high-energy polarimetry: Multi-band predictions and detectability

Sara Capecchiacci, Ioannis Liodakis, Haocheng Zhang +2

Polarimetric properties of blazars provide key constraints on the acceleration mechanisms powering their relativistic jets, the high-energy emission processes involved, and the com…

astro-ph.HE2026

Detailed Timing, Spectral, and Polarimetric Analysis of Magnetar 1RXS J170849.0-400910

Rachael Stewart, George Younes, Alice Harding +5

We present a broadband timing, spectral, and polarimetric study of the magnetar 1RXS~J170849.0-400910 using XMM-Newton, NuSTAR, and IXPE. The pulse morphology evolves strongly acro…

astro-ph.HE2026★ 2 cited

Gamma-ray signature of superluminous supernovae: Fermi-LAT GeV detection of SN 2017egm and evidence of a central engine

F. Acero, A. Acharyya, A. Adelfio +116

Superluminous supernovae (SLSNe) are a rare class of transients with peak luminosities 10-100 times greater than those of standard core-collapse supernovae (SNe). The mechanisms po…

astro-ph.HE2026

Magnetar Fireballs and Short Bursts: Curved Spacetime Lensing, QED Effects, Spectra, Polarization, and Impulse Responses

Zorawar Wadiasingh, Hoa Dinh Thi, Constantinos Kalapotharakos +12

Magnetar short bursts (SBs) are hard X-ray transients of durations s peaking at keV, and are prime targets for new high-energy missions and polarimeters. The…

astro-ph.HE2026

Label Propagation for Identifying Gamma-Ray Burst Progenitors from Prompt Emission

Skye Strain, Nicoló Cibrario, Michela Negro +1

Gamma-ray bursts (GRBs) are the most energetic bursts of light in our universe, and rapid progenitor association of these events can lead to targeted and optimized follow-up observ…

astro-ph.HE2026

High-Energy Shock Breakout from Supernovae and Gamma-ray Bursts

Chris L. Fryer, Eric Burns, Joseph M. Colosimo +2

Cosmic explosions play a critical role in a broad range of astrophysical fields. Although considerable progress has been made to understand the explosive engines and their progenit…

astro-ph.HE2026

Magnetic-field Order in the Southwestern Rim of RCW 86 Constrained Using X-Ray Polarimetry

Stefano Silvestri, Dmitry Prokhorov, Jacco Vink +97

RCW 86 is a supernova remnant whose origin has recently been linked to an off-center explosion within a cavity created by its progenitor star. In the southwestern region, the forwa…

astro-ph.HE2025

From Rare Events to a Population: Discovering Overlooked Extragalactic Magnetar Giant Flare Candidates in Archival Fermi Gamma-ray Burst Monitor Data

Aaron C. Trigg, Eric Burns, Michela Negro +16

Magnetar giant flares (MGFs) are rare, extremely bright bursts of gamma-rays from highly magnetized neutron stars. These events are challenging to identify because, at extragalacti…

astro-ph.HE2025

Fast X-ray Transient Detection with AXIS: application to Magnetar Giant Flares

Michela Negro, Zorawar Wadiasingh, George Younes +6

Magnetar giant flares (MGFs) are among the most luminous high-energy transients in the local universe, consisting of a short, intense MeV gamma-ray spike followed by a softer, puls…

astro-ph.HE2025★ 1 cited

Embedding Reliability for Unsupervised Classification of Gamma Ray Burst progenitors from Prompt Gamma-ray Emission

Nicoló Cibrario, Michela Negro

We present a statistical method based on scDEED to assess the reliability of a 2D embedding showing a low-dimensional representation of the distribution of Gamma-Ray Bursts (GRBs)…

astro-ph.HE2025

Direct observation of the X-ray counterpart of the Hα filaments and of the sloshing spiral in the Perseus galaxy cluster

Adrien Picquenot, Fabio Acero, Valeria Olivares +2

Deep Chandra observations of the Perseus galaxy cluster have allowed for the discovery of X-ray counterparts to the Hα filamentary structures and of a sloshing spiral. However, bot…

astro-ph.HE2025★ 12 cited

GRB 250702B: Discovery of a Gamma-Ray Burst from a Black Hole Falling into a Star

Eliza Neights, Eric Burns, Chris L. Fryer +52

Gamma-ray bursts are the most luminous electromagnetic events in the universe. Their prompt gamma-ray emission has typical durations between a fraction of a second and several minu…

astro-ph.HE2025★ 4 cited

Vacuum birefringence and the polarized X-ray emission from a radio magnetar

Rachael E. Stewart, Hoa Dinh Thi, George Younes +13

Magnetars are isolated neutron stars with exceptionally strong surface fields exceeding G. Their bright X-ray emission probes physical regimes in which quantum electrodyn…

astro-ph.HE2025

Testing Magnetic Field Configurations in Spider Pulsar PSR J1723-2837 with IXPE

Michela Negro, Haocheng Zhang, Niccolò Di Lalla +4

We present the first X-ray polarimetry observations of a redback millisecond pulsar binary, PSR J1723-2837, with the Imaging X-ray Polarimetry Explorer (IXPE). We conduct a spectro…

astro-ph.HE2025

Mapping Gamma-Ray Bursts: Distinguishing Progenitor Systems Through Machine Learning

Sharleen N. Espinoza, Nicole M. Lloyd-Ronning, Michela Negro +2

We present an analysis of gamma-ray burst (GRB) progenitor classification, through their positions on a Uniform Manifold Approximation and Projection (UMAP) plot, constructed by Ne…

astro-ph.HE2025★ 1 cited

Precision spectral measurements of Chromium and Titanium from 10 to 250 GeV and sub-Iron to Iron ratio with the Calorimetric Electron Telescope on the ISS

O. Adriani, Y. Akaike, K. Asano +77

The Calorimetric Electron Telescope (CALET), in operation on the International Space Station since 2015, collected a large sample of cosmic-ray (CR) iron and sub-iron events over a…

astro-ph.HE2025★ 2 cited

Puzzling Variation of Gamma Rays from the Sun over the Solar Cycle Revealed with Fermi-LAT

A. Acharyya, A. Adelfio, M. Ajello +100

The steady-state gamma-ray emission from the Sun is thought to consist of two emission components due to interactions with Galactic cosmic rays: (1) a hadronic disk component, and…

astro-ph.HE2025★ 1 cited

Multidisciplinary Science in the Multimessenger Era

Eric Burns, Christopher L. Fryer, Ivan Agullo +82

Astrophysical observations of the cosmos allow us to probe extreme physics and answer foundational questions on our universe. Modern astronomy is increasingly operating under a hol…

astro-ph.HE2025

Timing and Spectral Evolution of the Magnetar 1E 1841-045 in Outburst

G. Younes, S. K. Lander, M. G. Baring +19

We present the timing and spectral analyses of the NICER, NuSTAR, and IXPE observations of the magnetar 1E 1841-045 covering 82 days following its August 2024 bursting activity as…

astro-ph.HE2025

Characterizing Candidate Blazar Counterparts of the Ultra-High-Energy Event KM3-230213A

KM3NeT Collaboration, MessMapp Group, LAT Collaboration +13

High-energy astrophysical neutrinos serve as crucial messengers for understanding hadronic acceleration processes and identifying the origins of cosmic rays, with blazars among the…

astro-ph.HE2024★ 1 cited

Extragalactic Magnetar Giant Flares: Population Implications, Rates and Prospects for Gamma-Rays, Gravitational Waves and Neutrinos

Paz Beniamini, Zorawar Wadiasingh, Aaron Trigg +5

Magnetar Giant Flares (MGFs) are the most energetic non-catastrophic transients known to originate from stellar objects. The first discovered events were nearby. In recent years, s…

astro-ph.HE2024

The role of magnetar transient activity in time-domain and multimessenger astronomy

Michela Negro, George Younes, Zorawar Wadiasingh +3

Time-domain and multimessenger astronomy (TDAMM) involves the study of transient and time-variable phenomena across various wavelengths and messengers. The Astro2020 Decadal Survey…

astro-ph.HE2024★ 7 cited

Prompt GRB recognition through waterfalls and deep learning

Michela Negro, Nicoló Cibrario, Eric Burns +3

Gamma-ray Bursts (GRBs) are one of the most energetic phenomena in the cosmos, whose study probes physics extremes beyond the reach of laboratories on Earth. Our quest to unravel t…