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19912026
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337 papers · 1 filter

astro-ph.HE2026

Legacy analysis of Milky Way dwarf spheroidal satellite galaxies: an update

A. Circiello, M. Di Mauro, M. Ajello +3

Studies of Fermi-Large Area Telescope (LAT) data coincident with dwarf spheroidal satellite galaxies (dSphs) of the Milky Way (MW) have put the most stringent constraints on models…

astro-ph.HE2026★ 1 cited

Locating the missing large-scale emission in the jet of M87* with short EHT baselines

Boris Georgiev, Paul Tiede, Sebastiano D. von Fellenberg +280

In Very-Long Baseline Interferometric arrays, nearly co-located stations probe the largest scales and typically cannot resolve the observed source. In the absence of large-scale st…

astro-ph.HE2026

The DESI Transients Survey: Legacy Classifications and Methodology

Xander J. Hall, Antonella Palmese, Segev BenZvi +56

We present the first systematic spectroscopic observations of extragalactic transients from the Dark Energy Spectroscopic Instrument (DESI), as part of the DESI Transients Survey p…

astro-ph.HE2026

Early results in the search for extreme coronal line emitters with the Dark Energy Spectroscopic Instrument

Peter Clark, Joseph Callow, Or Graur +44

Here we present the results of our search through the Early Data Release (EDR) of the Dark Energy Spectroscopic Instrument (DESI) for extreme coronal line emitters (ECLEs) - a rare…

astro-ph.HE2025★ 4 cited

Probing jet base emission of M87* with the 2021 Event Horizon Telescope observations

Saurabh, Hendrik Müller, Sebastiano D. von Fellenberg +282

We investigate the presence and spatial characteristics of the jet base emission in M87* at 230 GHz, enabled by the enhanced uv coverage in the 2021 Event Horizon Telescope (EHT) o…

astro-ph.HE2025★ 2 cited

Acceleration of Heavy Ions at Non-Relativistic Collisionless Shocks

Damiano Caprioli, Luca Orusa, Miha Cernetic +2

We investigate the process of Diffusive Shock Acceleration (DSA) of particles with mass number to charge number ratios , e.g., partially-ionized heavy ions. To this end, w…

astro-ph.HE2025★ 20 cited

Horizon-scale variability of M87* from 2017--2021 EHT observations

The Event Horizon Telescope Collaboration

We report three epochs of polarized images of M87* at 230\,GHz using data from the Event Horizon Telescope (EHT) taken in 2017, 2018, and 2021. The baseline coverage of the 2021 ob…

astro-ph.HE2025★ 4 cited

Road map for the tuning of hadronic interaction models with accelerator-based and astroparticle data

Johannes Albrecht, Julia Becker Tjus, Noah Behling +52

In high-energy and astroparticle physics, event generators play an essential role, even in the simplest data analyses. As analysis techniques become more sophisticated, e.g. based…

astro-ph.HE2025★ 2 cited

The role of three-dimensional effects on ion injection and acceleration in perpendicular shocks

Luca Orusa, Damiano Caprioli, Lorenzo Sironi +1

Understanding the conditions that enable particle acceleration at non-relativistic collisionless shocks is essential to unveil the origin of cosmic rays. We employ 2D and 3D hybrid…

astro-ph.HE2025★ 10 cited

Kilonova constraints for the LIGO/Virgo/KAGRA neutron star merger candidate S250206dm: GW-MMADS observations

Lei Hu, Tomás Cabrera, Antonella Palmese +35

Gravitational wave (GW) neutron star mergers with an associated electromagnetic counterpart constitute powerful probes of binary evolution, the production sites of heavy elements,…

astro-ph.HE2025★ 4 cited

Origin of the ring ellipticity in the black hole images of M87*

Rohan Dahale, Ilje Cho, Kotaro Moriyama +273

We investigate the origin of the elliptical ring structure observed in the images of the supermassive black hole M87*, aiming to disentangle contributions from gravitational, astro…

astro-ph.HE2025★ 1 cited

Dark Matter and Galaxy Cross-Correlations with the Cherenkov Telescope Array Observatory

Elena Pinetti, Veronika Vodeb, Aurelio Amerio +4

The Cherenkov Telescope Array Observatory (CTAO) will be a ground-based Cherenkov telescope performing wide-sky surveys, ideal for anisotropy studies such as cross-correlations wit…

astro-ph.HE2025★ 1 cited

First Observations of Solar Halo Gamma Rays Over a Full Solar Cycle

Tim Linden, Jung-Tsung Li, Bei Zhou +4

We analyze 15 years of Fermi-LAT data and produce a detailed model of the Sun's inverse-Compton scattering emission (solar halo), which is powered by interactions between ambient c…

astro-ph.HE2025★ 2 cited

Scaler rates from the Pierre Auger Observatory: a new proxy of solar activity

The Pierre Auger Collaboration, I. Bizzarri, C. Dionese +1

The modulation of low-energy galactic cosmic rays reflects interplanetary magnetic field variations and can provide useful information on solar activity. An array of ground-surface…

astro-ph.HE2025★ 2 cited

Plasma Instabilities Dominate Radioactive Transients Magnetic Fields: The self-confinement of leptons in Type Ia and Core-Collapse Supernovae, and Kilonovae

Dhvanil D. Desai, Colby C. Haggerty, Benjamin J. Shappee +8

The light curves of radioactive transients, such as supernovae and kilonovae, are powered by the decay of radioisotopes, which release high-energy leptons through and d…

astro-ph.HE2025★ 3 cited

Clash of the Titans: ultra-high energy KM3NeT event versus IceCube data

Shirley Weishi Li, Pedro Machado, Daniel Naredo-Tuero +1

KM3NeT has reported the detection of a remarkably high-energy through-going muon. Lighting up about a third of the detector, this muon likely originated from a neutrino exceeding 1…

astro-ph.HE2025★ 16 cited

Revealing an unexpectedly low electron injection threshold via reinforced shock acceleration

Savvas Raptis, Ahmad Lalti, Martin Lindberg +3

Collisionless shock waves, found in supernova remnants, interstellar, stellar, and planetary environments, and laboratories, are one of nature's most powerful particle accelerators…

astro-ph.HE2025★ 5 cited

A search for the anomalous events detected by ANITA using the Pierre Auger Observatory

The Pierre Auger Collaboration, A. Abdul Halim, P. Abreu +374

A dedicated search for upward-going air showers at zenith angles exceeding and energies EeV has been performed using the Fluorescence Detector of the Pierre Aug…

astro-ph.HE2025★ 7 cited

AT 2018dyk: tidal disruption event or active galactic nucleus? Follow-up observations of an extreme coronal line emitter with the Dark Energy Spectroscopic Instrument

Peter Clark, Joseph Callow, Or Graur +29

We present fresh insights into the nature of the tidal disruption event (TDE) candidate AT 2018dyk. AT 2018dyk has sparked a debate in the literature around its classification as e…

astro-ph.HE2025★ 10 cited

The putative center in NGC 1052

Anne-Kathrin Baczko, Matthias Kadler, Eduardo Ros +284

Many active galaxies harbor powerful relativistic jets, however, the detailed mechanisms of their formation and acceleration remain poorly understood. To investigate the area of je…

astro-ph.HE2025★ 13 cited

A multi-frequency study of sub-parsec jets with the Event Horizon Telescope

Jan Röder, Maciek Wielgus, Andrei P. Lobanov +287

The 2017 observing campaign of the Event Horizon Telescope (EHT) delivered the first very long baseline interferometry (VLBI) images at the observing frequency of 230 GHz, leading…

astro-ph.HE2024★ 5 cited

Direct nonparametric multimessenger constraints on the equation of state of cold dense nuclear matter

Iuliu Cuceu, Sandra Robles

We utilize the now substantial amount of astrophysical observations of neutron stars (NSs), along with perturbative quantum chromodynamics (pQCD) calculations at high density, to d…

astro-ph.HE2024★ 9 cited

Ultrahigh-energy neutrinos as a probe of espresso-shear acceleration in jets of Centaurus A

Rostom Mbarek, Damiano Caprioli, Kohta Murase

It has been suggested that Centaurus A (Cen A) could make a contribution to the observed ultrahigh-energy cosmic-ray (UHECR) flux. We calculate the flux of astrophysical neutrinos…

astro-ph.HE2024

Cross Correlating the Unresolved Gamma-Ray Background with Cosmic Large-Scale Structure from DESI: Implications for Astrophysics and Dark Matter

Bei Zhou, José Luis Bernal, Elena Pinetti +2

The unresolved gamma-ray background (UGRB) is a diffuse gamma-ray emission arising from numerous extragalactic sources below the detection threshold and is an important component o…