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TITLE:   GCN CIRCULAR
NUMBER:  21332
SUBJECT: GRB 170712A: Insight-HXMT detection
DATE:    17/07/13 08:03:16 GMT
FROM:    Shaolin Xiong at IHEP  <xiongsl@ihep.ac.cn>

L. M. Song, X. B. Li, S. L.Xiong, J. Y. Liao, X. Ma, 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), M. Gao (IHEP),
T. P. Li (IHEP/THU), M. S. Li, F. J. Lu, W. H. Tao, H. Y. Wang, X. Y. Wen,
M. Wu, Y. P. Xu, C. M. Zhang, F. Zhang, J. Zhang, T. Zhang,
S. N. Zhang (IHEP), report on behalf of the Insight-HXMT team:

During the commissioning phase, at 2017-07-12T03:20:30.00 (T0),
Insight-HXMT detected GRB 170712A (trigger ID: HEB170712139)
in a routine search of the data, which was also observed by
Konus-Wind (trig time: 2017-07-12T03:20:26.59).

The Insight-HXMT light curve consists of multiple pulses
with a duration (T90) of 8.6 s measured from T0-5.82 s.
The 1-second peak rate, measured from T0+0.5 s, is 1948.9 cnts/sec.
The total counts from this burst is 4455 counts.

All measurements above are made with the CsI detectors operating in the
GRB mode, in which the energy range is increased to about 200 - 3000 keV
(record energy) , compared to the normal mode of 80 - 800 keV.
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.

URL_LC: http://www.hxmt.org/images/GRB/HEB170712139_lc.jpg

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:
http://www.hxmt.org/index.php/enhome .

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TITLE:   GCN CIRCULAR
NUMBER:  21339
SUBJECT: GRB 170712A: AstroSat CZTI detection
DATE:    17/07/14 09:00:49 GMT
FROM:    Vidushi Sharma at IUCAA  <vidushi@iucaa.in>

V. Sharma (IUCAA), V. Bhalerao (IIT-B), D. Bhattacharya (IUCAA), 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-duration GRB 170712A, which was also detected by Insight-HXMT (Song et al., GCN 21332) and Konus-Wind (trig time: 2017-07-12 03:20:26.59).

The source was clearly detected in the 40-200 keV energy range. The light curve shows multiple peaks of emission with the strongest peak at 03:20:30 UT, ~1 s before the Insight-HXMT Trigger. The measured peak count rate is 198.6 cts/s above the background in combined data of four quadrants, with a total of 718 cts. The local mean background count rate was 349.8 cts/s. Using cumulative rates, we measure a T90 of 10.8 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.