[vsnet-grb-info 19846] GRB 170918A: Insight-HXMT detection

[GCN Circulars]

TITLE:   GCN CIRCULAR
NUMBER:  21911
SUBJECT: GRB 170918A: Insight-HXMT detection
DATE:    17/09/22 13:44:54 GMT
FROM:    Shaolin Xiong at IHEP  <xiongsl at ihep.ac.cn>

S. L. Xiong, X. B. Li, C. K. Li, 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:

During the commissioning phase, at 2017-09-18T21:43:35.40 (T0),
Insight-HXMT/HE detected GRB 170918A (trigger ID: HEB170918905)
in a routine search of the data. No other observation for this GRB has
been reported yet.

The Insight-HXMT light curve mainly consists of a single pulse
with a duration (T90) of 0.98 s measured from T0+0.068 s.
The 100-ms peak rate, measured from T0+0.056 s, is 2278.3 cnts/sec.
The total counts from this burst is 1217.5 counts.

URL_LC: http://www.hxmt.org/images/GRB/HEB170918905_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.

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 .