172 citations · 756 across the 27 of their papers we have counts for
22 papers · 1 filter
The peculiar new state of the blazar PKS 1510-089
H. M. Schutte, M. Zacharias, M. Böttcher +4
Contemporaneous multiwavelength observations with H.E.S.S., SALT, Fermi-LAT, Swift, and ATOM show that the blazar PKS 1510-089 suffered a significant decrease in its optical flux,…
Multiwavelength Observations of the Blazar PKS~0735+178 in Spatial and Temporal Coincidence with an Astrophysical Neutrino Candidate IceCube-211208A
M. Pohl, K. Mori
We report on multiwavelength target-of-opportunity observations of the blazar PKS 0735+178, located 2.2 degrees away from the best-fit position of the IceCube neutrino event 211208…
The vanishing of the primary emission region in PKS 1510-089
F. Aharonian, F. Ait Benkhali, J. Aschersleben +152
In July 2021, PKS 1510-089 exhibited a significant flux drop in the high-energy gamma-ray (by a factor 10) and optical (by a factor 5) bands and remained in this low state througho…
Multiwavelength Observations of the Blazar PKS 0735+178 in Spatial and Temporal Coincidence with an Astrophysical Neutrino Candidate IceCube-211208A
A. Acharyya, C. B. Adams, A. Archer +207
We report on multiwavelength target-of-opportunity observations of the blazar PKS 0735+178, located 2.2 away from the best-fit position of the IceCube neutrino event IceCub…
Constraints on the intergalactic magnetic field using Fermi-LAT and H.E.S.S. blazar observations
H. E. S. S., Fermi-LAT Collaborations, : +134
Magnetic fields in galaxies and galaxy clusters are believed to be the result of the amplification of intergalactic seed fields during the formation of large-scale structures in th…
Constraining the cosmic-ray pressure in the inner Virgo Cluster using H.E.S.S. observations of M 87
H. E. S. S. Collaboration, :, F. Aharonian +160
The origin of the gamma-ray emission from M87 is currently a matter of debate. This work aims to localize the VHE (100 GeV-100 TeV) gamma-ray emission from M87 and probe a potentia…
Detection of extended gamma-ray emission around the Geminga pulsar with H.E.S.S
H. E. S. S. Collaboration, :, F. Aharonian +165
Geminga is an enigmatic radio-quiet gamma-ray pulsar located at a mere 250 pc distance from Earth. Extended very-high-energy gamma-ray emission around the pulsar was discovered by…
H.E.S.S. follow-up observations of GRB221009A
H. E. S. S. Collaboration, :, F. Aharonian +159
GRB221009A is the brightest gamma-ray burst ever detected. To probe the very-high-energy (VHE, \!100 GeV) emission, the High Energy Stereoscopic System (H.E.S.S.) began observat…
Contrasting X-ray/UV time-lags in Seyfert 1 galaxies NGC 4593 and NGC 7469 using AstroSat observations
Kavita Kumari, G. C. Dewangan, I. E. Papadakis +6
We study accretion disk-corona connection in Seyfert 1 galaxies using simultaneous UV/X-ray observations of NGC 4593 (July 14-18, 2016) and NGC 7469 (October 15-19, 2017) performed…
A multiwavelength study of the flat spectrum radio-quasar NVSS J141922-083830 covering four flaring episodes
D. A. H. Buckley, R. J. Britto, S. Chandra +9
We present multiwavelength observations and a model for flat spectrum radio quasar NVSS J141922-083830, originally classified as a blazar candidate of unknown type (BCU II object)…
A deep spectromorphological study of the -ray emission surrounding the young massive stellar cluster Westerlund 1
F. Aharonian, H. Ashkar, M. Backes +156
Young massive stellar clusters are extreme environments and potentially provide the means for efficient particle acceleration. Indeed, they are increasingly considered as being res…
Searching for TeV gamma-ray emission from SGR\,1935+2154 during its 2020 X-ray and radio bursting phase
H. E. S. S. Collaboration, :, H. Abdalla +251
Magnetar hyperflares are the most plausible explanation for fast radio bursts (FRB) -- enigmatic powerful radio pulses with durations of several milliseconds and high brightness te…
Evidence of 100 TeV -ray emission from HESS J1702-420: A new PeVatron candidate
L. Giunti, B. Khelifi, K. Kosack +1
The identification of active PeVatrons, hadronic particle accelerators reaching the knee of the cosmic-ray spectrum (at the energy of few PeV), is crucial to understand the origin…
LMC N132D: A mature supernova remnant with a power-law gamma-ray spectrum extending beyond 8 TeV
H. E. S. S. Collaboration, :, H. Abdalla +233
We analyzed 252 hours of High Energy Stereoscopic System (H.E.S.S.) observations towards the supernova remnant (SNR) LMC N132D that were accumulated between December 2004 and March…
Search for dark matter annihilation signals from unidentified Fermi-LAT objects with H.E.S.S
H. E. S. S. Collaboration, H. Abdallah, F. Aharonian +226
Cosmological -body simulations show that Milky Way-sized galaxies harbor a population of unmerged dark matter subhalos. These subhalos could shine in gamma-rays and be eventuall…
Revealing x-ray and gamma ray temporal and spectral similarities in the GRB 190829A afterglow
H. E. S. S. Collaboration
Gamma-ray bursts (GRBs), which are bright flashes of gamma rays from extragalactic sources followed by fading afterglow emission, are associated with stellar core collapse events.…
Search for dark matter annihilation in the dwarf irregular galaxy WLM with H.E.S.S
H. E. S. S. Collaboration, H. Abdallah, R. Adam +232
We search for an indirect signal of dark matter through very high-energy gamma rays from the Wolf-Lundmark-Melotte (WLM) dwarf irregular galaxy. The pair annihilation of dark matte…
Broadband Multi-wavelength Properties of M87 during the 2017 Event Horizon Telescope Campaign
J. C. Algaba, J. Anczarski, K. Asada +36
In 2017, the Event Horizon Telescope (EHT) Collaboration succeeded in capturing the first direct image of the center of the M87 galaxy. The asymmetric ring morphology and size are…
Search for dark matter signals towards a selection of recently-detected DES dwarf galaxy satellites of the Milky Way with H.E.S.S
H. E. S. S. Collaboration, :, H. Abdallah +227
Dwarf spheroidal galaxy satellites of the Milky Way are prime targets for indirect detection of dark matter with gamma rays due to their proximity, high dark matter content and abs…
Probing the magnetic field in the GW170817 outflow using H.E.S.S. observations
H. E. S. S. Collaboration, :, H. Abdalla +230
The detection of the first electromagnetic counterpart to the binary neutron star (BNS) merger remnant GW170817 established the connection between short -ray bursts and BNS merg…
Very high energy -ray emission from two blazars of unknown redshift and upper limits on their distance
H. E. S. S. Collaboration, H. Abdalla, R. Adam +225
We report on the detection of very-high-energy (VHE; GeV) -ray emission from the BL Lac objects KUV 00311-1938 and PKS 1440-389 with the High Energy Stereoscopic Syste…
H.E.S.S. and Suzaku observations of the Vela X pulsar wind nebula
H. E. S. S. Collaboration
Pulsar Wind Nebulae (PWNe) represent the most prominent population of Galactic very-high-energy gamma-ray sources and are thought to be an efficient source of leptonic cosmic rays.…