{
  "bibcode": "2021GCN.30697....1O",
  "body": "M. Ohno (Eotvos U./Konkoly Observatory/Hiroshima U.), J. Ripa (Masaryk U.),\n H. Takahashi (Hiroshima U.), A. Pal, L. Meszaros, B. Csak (Konkoly\nObservatory), N. Werner, M. Topinka, F. Munz, F. Hroch (Masaryk U.), T.\nUrbanec, M. Kasal,  A. Povalac (Brno U. of Technology), J. Hudec, J. Kapus,\nM. Frajt (Spacemanic s.r.o), R. Laszlo, M. Koleda (Needronix s.r.o), M.\nSmelko, P. Hanak, P. Lipovsky (Technical U. of Kosice), G. Galgoczi (Wigner\nResearch Center/Eotvos U.), Yuusuke Uchida, Helen Poon, H. Matake, N.\nUchida (Hiroshima U.), T. Bozoki (Eotvos U.), G. Dalya (Eotvos U.), T.\nEnoto (Kyoto U.), Zs. Frei (Eotvos U.), G. Friss (Eotvos U.), Y. Fukazawa,\nK. Hirose (Hiroshima U.), S. Hisadomi (Nagoya U.), Y. Ichinohe (Rikkyo U.),\nK. Kapas (Eotvos U.), L. L. Kiss (Konkoly Observatory),  T. Mizuno\n(Hiroshima U.), K. Nakazawa (Nagoya U.), H. Odaka (Univ of Tokyo), J.\nTakatsy (Eotvos U.), K. Torigoe (Hiroshima U.) -- the GRBAlpha\ncollaboration.\n\nThe long duration GRB 210822A (Swift-BAT detection; Page et al. GCN Circ.\n 30677, GECAM detection; Wang et al. GCN Circ. 30678, Fermi-LAT detection;\nOhno et al. GCN Circ. 30687) was detected by the GRBAlpha 1U CubeSat (Pal\net al. Proc. SPIE 2020).\n\nThe light curve shows a strong spike structure with a high significance of\na SNR ~ 45. The observed total duration was about 12 sec. GRBAlpha was\nleaving the outer Van Allen radiation belt and thus GRB 210822A is\nsuperimposed on a high background due to trapped electrons.\n\nThe light curve obtained by GRBAlpha is available here:\nhttps://grbalpha.konkoly.hu/static/share/GRB210822A_GCN.pdf\n\nGRBAlpha is a demonstration mission for a future CubeSats constellation\n(Werner et al. Proc. SPIE 2018). The detector of GRBAlpha consists of a 75\nx 75 x 5 mm3 CsI scintillator read out by a SiPM array, covering the energy\nrange from ~50 keV to ~1000 keV. GRBAlpha was launched on 2021 March 22\nfrom Baikonur. After its commissioning phase, the scientific observations\nare now under way. To increase the duty cycle and the downlink rate, the\nupgrade of the on-board data acquisition software stack is in progress. The\nground segment is also supported by the radio amateur community and it\ntakes advantage of the SatNOGS network for increased data downlink volume.",
  "circularId": 30697,
  "createdOn": 1629733338000,
  "email": "ohno@astro.hiroshima-u.ac.jp",
  "subject": "GRB 210822A: Detection by GRBAlpha",
  "submitter": "Masanori Ohno at Hiroshima U  <ohno@astro.hiroshima-u.ac.jp>",
  "eventId": "GRB 210822A"
}