GCN Circular 33218

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 short-duration GRB 230114B (Konus-Wind detection trigger time at 
2023-01-14 20:40:57.752 UT; INTEGRAL/SPI-ACS detection peak at 
~2023-01-14 20:40:56 UT) was detected by the GRB detector on board of 
the VZLUSAT-2 3U CubeSat (https://www.vzlusat2.cz/en/).

The data acquisition was performed by GRB detector unit no. 1 and the 
detection was confirmed at the peak time 2023-01-14 20:40:54 UTC. The 
duration was measured to be 1 s with the light curve resolution of 1 s. 
The significance is 4.9 sigma.

The light curve obtained by VZLUSAT-2 is available here:
https://vzlusat2.konkoly.hu/static/share/GRB230114B_GCN_VZLUSAT2.pdf

All VZLUSAT-2 detections are listed at: 
https://monoceros.physics.muni.cz/hea/VZLUSAT-2/
The 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.