7 papers
Gamma-Ray Constraints on Heavy Axion-Like-Particle Decays from Fermi-LAT and H.E.S.S. Blazar Spectra
A. Acharyya, F. Aharonian, M. Backes +117
The propagation of very-high-energy (VHE; GeV) gamma rays from extragalactic sources is affected by interactions with photons of the extragalactic background light…
H.E.S.S. observations of composite Seyfert-starburst galaxies
H. E. S. S. Collaboration, A. Acharyya, F. Aharonian +119
Context: Composite galaxies that contain both Seyfert and starburst components may produce very high-energy (VHE; >100 GeV) gamma-ray emission at a wide range of spatial scales, fr…
Scrutinizing the 2020 multiwavelength outburst of PKS 0903-57 through observations with H.E.S.S
A. Acharyya, F. Aharonian, F. Ait Benkhali +138
The blazar PKS 0903-57 has recently been classified as a flat spectrum radio quasar at a redshift of . In March and April 2020, Fermi-LAT and AGILE reported tremendous ac…
Prompt Searches for Very-High-Energy γ-Ray Counterparts to IceCube Astrophysical Neutrino Alerts
J. Abhir, A. Biland, K. Brand +817
The search for sources of high-energy astrophysical neutrinos can be significantly advanced through a multi-messenger approach, which seeks to detect the gamma rays that accompany…
Constraining the nature of the most extreme Galactic particle accelerator. H.E.S.S. observations of the microquasar V4641 Sgr
A. Acharyya, F. Aharonian, H. Ashkar +131
Microquasars have emerged as promising candidates to explain the cosmic-ray flux at petaelectronvolt energies. LHAASO observations revealed V4641~Sgr as the most extreme example so…
The H.E.S.S. extragalactic sky survey with the first decade of observations
H. E. S. S. Collaboration, F. Aharonian, F. Ait Benkhali +140
The results of the first extragalactic gamma-ray survey by the High Energy Stereoscopic System (H.E.S.S.) are presented. The survey comprises 2720 hours of very high-energy gamma-r…