GRB 190720B
GCN Circular 25254
Subject
GRB 190720B: AstroSat CZTI detection
Date
2019-08-02T11:25:01Z (6 years ago)
From
Prachee Ghumatkar at IUCAA/AstroSat <prachee@iucaa.in>
P. Ghumatkar, V. Sharma and D. Bhattacharya (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 190720B, which was also detected by Fermi GBM (GCN #25132) and Insight-HXMT/HE (Luo Q. et. al., GCN #25137).
The source was clearly detected in the 40-200 keV energy range. The light curve shows single pulse of emission with strongest peak at 23:08:40.0 UT. The measured peak count rate associated with the burst is 116 cts/s above the background in the combined data of four quadrants, with a total of 493 cts. The local mean background count rate was 507 cts/s. Using cumulative rates, we measure a T90 of 8.5 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.
GCN Circular 25137
Subject
GRB 190720B: Insight-HXMT/HE detection
Date
2019-07-21T14:32:36Z (6 years ago)
From
Qi Luo at IHEP <luoqi@ihep.ac.cn>
Q. Luo, C. Cai, S. Xiao, Q. B. Yi, Y. G. Zheng, Y. Huang,
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 2019-07-20T23:08:39.50 (T0), Insight-HXMT/HE detected
GRB 190720B (trigger ID: HEB190720964) in a routine search of the data,
which was also triggered by Fermi/GBM (GCN #25132).
The Insight-HXMT/HE light curve mainly consists of a single
pulse with a duration (T90) of 8.59 s measured from T0-1.01 s.
The 1-ms peak rate, measured from T0-0.14 s, is 873 cnts/sec.
The total counts from this burst is 3465 counts.
URL_LC: http://www.hxmt.org/images/GRB/HEB190720964_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.
GCN Circular 25132
Subject
GRB 190720B: Fermi GBM Final Real-time Localization
Date
2019-07-20T23:20:09Z (6 years ago)
From
Fermi GBM Team at MSFC/Fermi-GBM <do_not_reply@GIOC.nsstc.nasa.gov>
The Fermi GBM team reports the detection of a likely LONG GRB
At 23:08:38 UT on 20 Jul 2019, the Fermi Gamma-ray Burst Monitor (GBM) triggered and located GRB 190720B (trigger 585356923.763906 / 190720964).
The on-ground calculated location, using the Fermi GBM trigger data, is RA = 138.9, Dec = -55.6 (J2000 degrees, equivalent to J2000 09h 15m, -55d 36'), with a statistical uncertainty of 2.4 degrees.
The angle from the Fermi LAT boresight is 54.0 degrees.
The skymap can be found here:
http://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2019/bn190720964/quicklook/glg_skymap_all_bn190720964.png
The HEALPix FITS file, including the estimated localization systematic, can be found here:
http://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2019/bn190720964/quicklook/glg_healpix_all_bn190720964.fit
The GBM light curve can be found here:
http://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2019/bn190720964/quicklook/glg_lc_medres34_bn190720964.gif