H.E.S.S. follow-up observations of GRB221009A
Abstract
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 observations 53 hours after the triggering event, when the brightness of the moonlight no longer precluded observations. We derive differential and integral upper limits using H.E.S.S. data from the third, fourth, and ninth nights after the initial GRB detection, after applying atmospheric corrections. The combined observations yield an integral energy flux upper limit of above GeV. The constraints derived from the H.E.S.S. observations complement the available multiwavelength data. The radio to X-ray data are consistent with synchrotron emission from a single electron population, with the peak in the SED occurring above the X-ray band. Compared to the VHE-bright GRB190829A, the upper limits for GRB221009A imply a smaller gamma-ray to X-ray flux ratio in the afterglow. Even in the absence of a detection, the H.E.S.S. upper limits thus contribute to the multiwavelength picture of GRB221009A, effectively ruling out an IC dominated scenario.
Keywords
Cite
@article{arxiv.2303.10558,
title = {H.E.S.S. follow-up observations of GRB221009A},
author = {H. E. S. S. Collaboration and : and F. Aharonian and F. Ait Benkhali and J. Aschersleben and H. Ashkar and M. Backes and A. Baktash and V. Barbosa Martins and R. Batzofin and Y. Becherini and D. Berge and K. Bernlöhr and B. Bi and M. Böttcher and C. Boisson and J. Bolmont and M. de Bony de Lavergne and J. Borowska and M. Bouyahiaoui and F. Bradascio and M. Breuhaus and R. Brose and F. Brun and B. Bruno and T. Bulik and C. Burger-Scheidlin and S. Caroff and S. Casanova and J. Celic and M. Cerruti and T. Chand and S. Chandra and A. Chen and J. Chibueze and O. Chibueze and G. Cotter and S. Dai and J. Damascene Mbarubucyeye and J. Devin and A. Djannati-Ataï and A. Dmytriiev and V. Doroshenko and K. Egberts and S. Einecke and J. -P. Ernenwein and S. Fegan and G. Fichet de Clairfontaine and M. Filipovic and G. Fontaine and M. Füßling and S. Funk and S. Gabici and S. Ghafourizadeh and G. Giavitto and D. Glawion and J. F. Glicenstein and P. Goswami and G. Grolleron and M. -H. Grondin J. A. Hinton and T. L. Holch and M. Holler and D. Horns and Zhiqiu Huang and M. Jamrozy and F. Jankowsky and V. Joshi and I. Jung-Richardt and E. Kasai and K. Katarzyński and R. Khatoon and B. Khélifi and W. Kluźniak and Nu. Komin and R. Konno and K. Kosack and D. Kostunin and R. G. Lang and S. Le Stum and F. Leitl and A. Lemière and M. Lemoine-Goumard and J. P. Lenain and F. Leuschner and T. Lohse and I. Lypova and J. Mackey and D. Malyshev and D. Malyshev and V. Marandon and P. Marchegiani and A. Marcowith and G. Martí-Devesa and R. Marx and M. Meyer and A. Mitchell and L. Mohrmann and A. Montanari and E. Moulin and T. Murach and K. Nakashima and M. de Naurois and J. Niemiec and A. Priyana Noel and P. O'Brien and S. Ohm and L. Olivera-Nieto and E. de Ona Wilhelmi and M. Ostrowski and S. Panny and M. Panter and R. D. Parsons and G. Peron and D. A. Prokhorov and H. Prokoph and G. Pühlhofer and M. Punch and A. Quirrenbach and P. Reichherzer and A. Reimer and O. Reimer and H. Ren and M. Renaud and B. Reville and F. Rieger and G. Rowell and B. Rudak and E. Ruiz-Velasco and V. Sahakian and H. Salzmann and A. Santangelo and M. Sasaki and J. Schäfer and F. Schüssler and H. M. Schutte and U. Schwanke and J. N. S. Shapopi and A. Specovius and S. Spencer and Ł. Stawarz and R. Steenkamp and S. Steinmassl and C. Steppa and I. Sushch and H. Suzuki and T. Takahashi and T. Tanaka and R. Terrier and N. Tsuji and Y. Uchiyama and M. Vecchi and C. Venter and J. Vink and S. J. Wagner and R. White and A. Wierzcholska and Yu Wun Wong and M. Zacharias and D. Zargaryan and A. A. Zdziarski and A. Zech and S. J. Zhu and N. Żywucka},
journal= {arXiv preprint arXiv:2303.10558},
year = {2023}
}
Comments
10 pages, 4 figures. Accepted for publication in APJL. Corresponding authors: J. Damascene Mbarubucyeye, H. Ashkar, S. J. Zhu, B. Reville, F. Sch\"ussler