Gamma-Ray Burst observations by the high-energy charged particle detector on board the CSES-01 satellite between 2019 and 2021
/ Authors
F. Palma, M. Martucci, C. Neubuser, A. Sotgiu, F. Follega, P. Ubertini, A. Bazzano, J. Rodi, R. Ammendola, D. Badoni
and 61 more authors
S. Bartocci, R. Battiston, S. Beolè, I. Bertello, W. J. Burger, D. Campana, A. Cicone, P. Cipollone, S. Coli, L. Conti, A. Contin, M. Cristoforetti, G. D’Angelo, F. D. Angelis, C. Donato, C. D. Santis, P. Diego, A. Luca, E. Fiorenza, G. Gebbia, R. Iuppa, A. Lega, M. Lolli, B. Martino, G. Masciantonio, M. Mergé, M. Mese, A. Morbidini, F. Nozzoli, F. Nuccilli, A. Oliva, G. Osteria, F. Palmonari, B. Panico, E. Papini, A. Parmentier, S. Perciballi, F. Perfetto, A. Perinelli, P. Picozza, M. Piersanti, M. Pozzato, G. Rebustini, D. Recchiuti, E. Ricci, Marco Ricci, S. Ricciarini, A. Russi, Z. Sahnoun, U. Savino, V. Scotti, Xuhui Shen, R. Sparvoli, S. Tofani, N. Vertolli, V. Vilona, V. Vitale, U. Zannoni, Z. Zeren, S. Zoffoli, P. Zuccon
/ Abstract
In this paper we report the detection of five strong Gamma-Ray Bursts (GRBs) by the High-Energy Particle Detector (HEPD-01) mounted on board the China Seismo-Electromagnetic Satellite (CSES-01), operational since 2018 on a Sun-synchronous polar orbit at a $\sim$ 507 km altitude and 97$^\circ$ inclination. HEPD-01 was designed to detect high-energy electrons in the energy range 3 - 100 MeV, protons in the range 30 - 300 MeV, and light nuclei in the range 30 - 300 MeV/n. Nonetheless, Monte Carlo simulations have shown HEPD-01 is sensitive to gamma-ray photons in the energy range 300 keV - 50 MeV, even if with a moderate effective area above $\sim$ 5 MeV. A dedicated time correlation analysis between GRBs reported in literature and signals from a set of HEPD-01 trigger configuration masks has confirmed the anticipated detector sensitivity to high-energy photons. A comparison between the simultaneous time profiles of HEPD-01 electron fluxes and photons from GRB190114C, GRB190305A, GRB190928A, GRB200826B and GRB211211A has shown a remarkable similarity, in spite of the different energy ranges. The high-energy response, with peak sensitivity at about 2 MeV, and moderate effective area of the detector in the actual flight configuration explain why these five GRBs, characterised by a fluence above $\sim$ 3 $\times$ 10$^{-5}$ erg cm$^{-2}$ in the energy interval 300 keV - 50 MeV, have been detected.