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GCN Circular 33088

GRB 221216A: Detection by VZLUSAT-2
2022-12-20T13:17:55Z (a year ago)
Jakub Ripa at Masaryk University <>
J. Ripa (Masaryk U.), A. Pal (Konkoly Observatory),�� N. Werner (Masaryk 
U.), M. Ohno (Hiroshima U.),�� L. Meszaros, B. Csak (Konkoly 
Observatory), H. Takahashi (Hiroshima U.), F. Munz , M. Topinka, F. 
Hroch, M. Dafcikova, N. Husarikova, J.-P. Breuer (Masaryk U.), J. Hudec, 
J. Kapus, M. Frajt, M. Rezenov (Spacemanic s.r.o), R. Laszlo 
(Needronix), G. Galgoczi (Wigner Research Center/Eotvos U.), N. Uchida 
(ISAS/JAXA), T. Enoto (Kyoto U.), Zs. Frei (Eotvos U.), Y. Fukazawa, K. 
Hirose, H. Matake (Hiroshima U.), S. Hisadomi (Nagoya U.), Y. Ichinohe 
(Rikkyo U.), L. L. Kiss (Konkoly Observatory),�� T. Mizuno (Hiroshima 
U.), K. Nakazawa (Nagoya U.), H. Odaka (Univ of Tokyo), K. Torigoe 
(Hiroshima U.), P. Svoboda, V. Daniel, J. Dudas, M. Junas, J. Gromes 
(VZLU), I. Vertat (FEL ZCU) -- the VZLUSAT-2/GRB payload collaboration.

The long-duration GRB 221216A (Fermi/GBM detection: Dunwoody et al., GCN 
Circ. 33077; Dichiara et al., GCN Circ. 33067; GECAM-B trigger num. 105) 
was detected by the GRB detector on board of the VZLUSAT-2 3U CubeSat 

The data acquisition was performed by GRB detector unit no. 1 and the 
count rate curve shows the peak time at 2022-12-16 11:21:28 UTC. The T90 
duration was measured to be 90 s with the light curve resolution of 1 s. 
The significance during T90 reaches 9.5 sigma.

The light curve obtained by VZLUSAT-2 is available here:

GRB detectors on VZLUSAT-2 are a demonstration payload for a future 
CubeSats constellation (Werner et al. Proc. SPIE 2018). Two GRB modules 
of VZLUSAT-2 are placed in a perpendicular manner and each consists of a 
75 x 75 x 5 mm3 CsI scintillator read out by a SiPM array, covering the 
energy range from ~30 keV to ~1000 keV. VZLUSAT-2 was launched on 2022 
January 13 from Cape Canaveral.
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