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TITLE:   GCN CIRCULAR
NUMBER:  23827
SUBJECT: GRB 190131A: AstroSat CZTI detection
DATE:    19/02/01 13:39:46 GMT
FROM:    Tanazza Khanam at IUCAA  <tanazza@iucaa.in>

T. Khanam, V. Sharma, D. Bhattacharya and  A. Vibhute (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 long GRB 190131A.

The source was clearly detected in the 20-200 keV energy range. The light curve shows multiple peaks of emission with the strongest peak at 23:08:38.5 UT. The measured peak count rate is 216 cts/s above the background in the combined data of four quadrants, with a total of 2804 cts. The local mean background count rate was 518 cts/s. Using cumulative rates, we measure a T90 of 17.6 s.

It was also 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.

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TITLE:   GCN CIRCULAR
NUMBER:  23828
SUBJECT: GRB 190131A: Insight-HXMT/HE detection
DATE:    19/02/01 14:48:23 GMT
FROM:    Ce Cai at IHEP  <caice@ihep.ac.cn>

C. Cai, 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, A. M. Zhang, 
Y. F. Zhang, X. F. Lu, 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 2019-01-31T23:08:35.000 (T0), the Insight-HXMT/HE detected 
GRB 190131A (trigger ID: HEB190131964) in a routine search of the data, 
which was also triggered by Fermi/GBM (trigger number 570668920);
AstroSAT (T. Khanam et al., GCN 23827); 

The Insight-HXMT/HE light curve mainly consists of multiple 
pulses with a duration (T90) of 23.40 s measured from T0+0.98 s. 
The 1-s peak rate, measured from T0+2.04 s, is 1371.5 cnts/s. 
The total counts from this burst is 15799.2 counts. 
URL_LC: http://www.hxmt.org/images/GRB/HEB190131964_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 could be found at: http://www.hxmt.org.