GRB 200703B

The Fermi GBM team reports the detection of a likely LONG GRB

At 23:16:41 UT on 3 Jul 2020, the Fermi Gamma-ray Burst Monitor (GBM) triggered and located GRB 200703B (trigger 615511006.839074 / 200703970).

The on-ground calculated location, using the Fermi GBM trigger data, is RA = 148.5, Dec = 6.3 (J2000 degrees, equivalent to J2000 09h 54m, 6d 17'), with a statistical uncertainty of 2.4 degrees.

The angle from the Fermi LAT boresight is 63.0 degrees.

The skymap can be found here:
https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2020/bn200703970/quicklook/glg_skymap_all_bn200703970.png

The HEALPix FITS file, including the estimated localization systematic, can be found here:
https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2020/bn200703970/quicklook/glg_healpix_all_bn200703970.fit

The GBM light curve can be found here:
https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2020/bn200703970/quicklook/glg_lc_medres34_bn200703970.gif

S. Gupta, V. Sharma and D. Bhattacharya (IUCAA), V. Bhalerao (IIT-B), A. R. Rao (IUCAA/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 200703B, which was also detected by Fermi GBM (GCN #28059
Loading...
 
 ).

The source was clearly detected in the 40-200 keV energy range. The light curve showed multiple peaks of emission with the strongest peak at 2020-07-03 23:17:06.531 UT. The measured peak count rate associated with the burst is 226 +/- 23 cts/s above the background in the combined data of four quadrants, with a total of 3165 +/- 66 cts. The local mean background count rate was 585 +/- 1 cts/s. Using cumulative rates, we measure a T90 of 31.58 +/- 0.35 s.

It was also clearly detected in the CsI anticoincidence (Veto) detector in the 100-500 keV energy range. The light curve showed multiple peaks of emission with the strongest peak at 2020-07-03 23:17:09.576 UT. The measured peak count rate is 733 +/- 42 cts/s above the background in the combined Veto data of four quadrants, with a total of 8880 +/- 119 cts. The local mean background count rate was 1808 +/- 2 cts/s.  We measure a T90 of 31.945 +/- 0.209 s from the cumulative Veto light curve.

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.

Q. Luo, Y. G. Zheng, C. Cai, S. Xiao, Q. B. Yi, W. C. Xue,
Y. Huang, C. K. Li, G. Li, X. B. 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 2020-07-03T23:16:52.80 (T0), Insight-HXMT/HE detected 
GRB 200703B (trigger ID: HEB200703970) in a routine search of the data, 
which was also triggered by Fermi/GBM (GCN #28059
Loading...
 
 ) and AstroSat/CZTI (GCN #28060
Loading...
 
 ).

The Insight-HXMT/HE light curve mainly consists of multiple 
pulses with a duration (T90) of 0.161 s measured from T0-11.360 s. 
The 1-ms peak rate, measured from T0+17.803 s, is 1950 cnts/sec. 
The total counts from this burst is 23638 counts.
URL_LC: http://twiki.ihep.ac.cn/pub/HXMT/GRBList/HEB200703970_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 (deposited 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 
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.