Y. Zhu, X. Ma, S. L. Xiong, X. B. Li, C. K. Li, Y. Huang, J. Y. Liao,
C. Z. Liu, X. F. Li, Z. W. Li, Z. Chang, X. F. Lu, J. L. Zhao, A. M. Zhang,
Y. F. Zhang, C. L. Zou (IHEP), Y. J. Jin, Z. Zhang (THU), T. P. Li (IHEP/THU),
F. J. Lu, L. M. Song, H. Y. Wang, M. Wu, Y. P. Xu, S. N. Zhang (IHEP),
report on behalf of the Insight-HXMT team:
At 2018-02-21T12:30:01.000 (T0), the Insight-HXMT detected
GRB 180221B (trigger ID: HEB180221520) in a routine search of the data,
which was also observed by CALET/CGBM (GCN Circ. 22438).
The Insight-HXMT light curve mainly consists of multi-pulses
with a duration (T90) of 65.8 s measured from T0+1.05 s.
The 1-second peak rate, measured from T0+13.0 s, is 2888.2 cnts/sec.
The total counts from this burst is 44805.8 counts.
All measurements above are made with the CsI detectors operating in the
regular mode with the energy range of about 80-800 keV (record energy).
Only gamma-rays with energy greater than about 200 keV can penetrate
the spacecraft and leave signals in the CsI detectors installed inside
of the telescope.
The analysis results presented above are preliminary;
final results will be published elsewhere.
Insight-HXMT is the first Chinese space X-ray telescope, which was funded
jointly by the China National Space Administration (CNSA) and the Chinese
Academy of Sciences (CAS). More information about it could be found at: