GRB 190326B
GCN Circular 24013
Subject
GRB 190326B: Fermi GBM detection
Date
2019-03-26T13:54:58Z (6 years ago)
From
Andreas von Kienlin at MPE <azk@mpe.mpg.de>
A. von Kienlin (MPE) reports on behalf of the Fermi GBM Team:
"At 07:31:39.00 UT on 26 March 2019, the Fermi Gamma-Ray Burst Monitor
triggered and located GRB 190326B (trigger 575278303 / 190326314).
The on-ground calculated location, using the GBM trigger data,
is RA = 264.2, DEC = 68.3 (J2000 degrees, equivalent
to 17h 37m, 68d 18'), with an uncertainty of 1.3 degrees
(radius, 1-sigma containment, statistical only; there is additionally a
systematic error which we have characterized as a core-plus-tail model,
with 90% of GRBs having a 3.7 deg error and a small tail suffering a
larger than 10 deg systematic error. [Connaughton et al. 2015, ApJS, 216, 32] ).
The angle from the Fermi LAT boresight at the GBM trigger time is 21 degrees.
The GBM light curve consists of multiple pulses with a duration (T90)
of about 56 s (50-300 keV). The time-averaged spectrum from
T0-2.048 s to T0+59.393 s is best fit by a Band function with Epeak = 163 +/- 14 keV,
alpha = -0.33 +/- 0.10, and beta = -1.93 +/- 0.07
The event fluence (10-1000 keV) in this time interval is
(1.78 +/- 0.05)E-05 erg/cm^2. The 1.024-sec peak photon flux measured
starting from T0+56.5128 s in the 10-1000 keV band
is 7.8 +/- 0.3 ph/s/cm^2.
The spectral analysis results presented above are preliminary;
final results will be published in the GBM GRB Catalog."
GCN Circular 24019
Subject
GRB 190326B: Insight-HXMT/HE detection
Date
2019-03-27T14:07:43Z (6 years ago)
From
Qi Luo at IHEP <luoqi@ihep.ac.cn>
Q. Luo, 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, X. F. Lu,
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,
M. Wu, Y. P. Xu, S. N. Zhang (IHEP),
report on behalf of the Insight-HXMT team:
At 2019-03-26T07:31:47.000 (T0), the Insight-HXMT/HE detected
GRB 190326B(trigger ID: HEB190326313) in a routine search of the data,
which was also triggered by Fermi/GBM(A. von Kienlin et al. ,GCN 24013).
The Insight-HXMT/HE light curve mainly consists of multiple
pulses with a duration (T90) of 58.45 s measured from T0+0.47 s.
The 1-ms peak rate, measured from T0+48.526 s, is 3079 cnts/sec.
The total counts from this burst is 28802 counts.
URL_LC: http://www.hxmt.org/images/GRB/HEB190326313_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 about it could be found at:
http://www.hxmt.org.
GCN Circular 24042
Subject
GRB 190326B: AstroSat CZTI detection
Date
2019-04-02T17:13:12Z (6 years ago)
From
Vidushi Sharma at IUCAA <vidushi@iucaa.in>
V. Sharma, D. Bhattacharya, A. Vibhute and T. Khanam (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 bright GRB 190326B, which was also detected by Fermi-GBM (Kienlin A. von et al., GCN # 24013) and Insight-HXMT/HE detection (Luo Q. et al., GCN # 24019).
The source was clearly detected in the 40-200 keV energy range. The light curve shows multiple pulses of emission with strongest peak at 07:32:36.5 UT. The measured peak count rate associated with the burst is 418 cts/s above the background in the combined data of four quadrants, with a total of 4932 cts. The local mean background count rate was 630 cts/s. Using cumulative rates, we measure a T90 of 54.3 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.