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TITLE:   GCN CIRCULAR
NUMBER:  24037
SUBJECT: GRB 190331C: Insight-HXMT/HE detection
DATE:    19/04/01 13:51:32 GMT
FROM:    Qi Luo at IHEP  <luoqi@ihep.ac.cn>

Q. Luo, C. K. Li, X. B. Li, G. Li, J. Y. Liao, S. L. Xiong,
C. Z. Liu, X. F. Li, Z. W. Li, Z. Chang, X. F. Lu,
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,
M. Wu, Y. P. Xu, S. N. Zhang (IHEP),
report on behalf of the Insight-HXMT team:

At 2019-03-31T20:12:00.100 (T0), the Insight-HXMT/HE detected
GRB 190331C(trigger ID: HEB190331841) in a routine search of the data,
which was also triggered by INTEGRAL.

The Insight-HXMT/HE light curve mainly consists of one
pulse with a duration (T90) of 0.24 s measured from T0+0.04 s.
The 1-ms peak rate, measured from T0+0.050 s, is 4679 cnts/sec.
The total counts from this burst is 315 counts.
URL_LC: http://www.hxmt.org/images/GRB/HEB190331841_lc.jpg

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.

Insight-HXMT is the first Chinese space X-ray telescope, which was
fundedjointly by the China National Space Administration (CNSA) and
the Chinese Academy of Sciences (CAS).
More information about it could be found at:
http://www.hxmt.org.

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TITLE:   GCN CIRCULAR
NUMBER:  24053
SUBJECT: GRB 190331C: AstroSat CZTI detection
DATE:    19/04/05 12:15:21 GMT
FROM:    Vidushi Sharma at IUCAA  <vidushi@iucaa.in>

V. Sharma, D. Bhattacharya, A. Vibhute and T. Khanam (IUCAA), V. Bhalerao (IIT-B), A. R. Rao (TIFR) and S. Vadawale (PRL) report on behalf of the AstroSat CZTI collaboration:

Analysis of AstroSat CZTI data showed the detection of a short GRB 190331C, which was also detected by Insight-HXMT/HE detection (Luo Q. et al., GCN # 24037).

The source was clearly detected in the 40-200 keV energy range. The light curve shows single peak of emission at 20:12:00.155 UT. The measured peak count rate associated with the burst is 2002 cts/s above the background in the combined data of four quadrants, with a total of 1648 cts. The local mean background count rate was 498 cts/s. Using cumulative rates, we measure a T90 of 0.16 s.

It was also clearly detected in the CsI anticoincidence (Veto) detector in the 100-500 keV energy range.

CZTI GRB detections are reported regularly on the payload site at http://astrosat.iucaa.in/czti/?q=grb. CZTI is built by a TIFR-led consortium of institutes across India, including VSSC, ISAC, IUCAA, SAC and PRL. The Indian Space Research Organisation funded, managed and facilitated the project.