GRB 230128A
GCN Circular 33235
Subject
GRB 230128A: AstroSat CZTI detection
Date
2023-01-30T09:22:07Z (3 years ago)
From
Gaurav Waratkar at IIT,Bombay <gauravwaratkar@iitb.ac.in>
P K. Navaneeth (IUCAA), R. Gopalakrishnan (IUCAA), G. Waratkar (IITB),
A. Vibhute (IUCAA), V. Bhalerao (IITB), D. Bhattacharya (Ashoka
University/IUCAA), A. R. Rao (IUCAA/TIFR), and S. Vadawale (PRL) report
on behalf of the AstroSat CZTI collaboration:
Analysis of AstroSat CZTI data with the CIFT framework (Sharma et al.,
2021, JApA, 42, 73) showed the detection of a long GRB230128A which was
also detected by Fermi GBM (GCN Circ. 33231).
It was clearly detected in the CsI anticoincidence (Veto) detector in
the 100-500 keV energy range. The light curve peaks at 2023-01-28
22:48:33.09 UTC. The measured peak count rate is 669 (+68, -52) counts/s
above the background in the combined Veto data of all quadrants, with a
total of 9446 (+1558, -2165) counts. The local mean background count
rate was 2912 (+3, -5) counts/s. We measure a T90 of 53 (+12, -16) 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, URSC, IUCAA, SAC,
and PRL. The Indian Space Research Organisation funded, managed, and
facilitated the project.
GCN Circular 33231
Subject
GRB 230128A: Fermi GBM Final Real-time Localization
Date
2023-01-28T22:57:57Z (3 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 22:47:49 UT on 28 Jan 2023, the Fermi Gamma-ray Burst Monitor (GBM) triggered and located GRB 230128A (trigger 696638874.07722 / 230128950).
The on-ground calculated location, using the Fermi GBM trigger data, is RA = 197.6, Dec = 61.7 (J2000 degrees, equivalent to J2000 13h 10m, 61d 42'), with a statistical uncertainty of 6.3 degrees.
The angle from the Fermi LAT boresight is 90.0 degrees.
The skymap can be found here:
https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2023/bn230128950/quicklook/glg_skymap_all_bn230128950.png
The HEALPix FITS file, including the estimated localization systematic, can be found here:
https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2023/bn230128950/quicklook/glg_healpix_all_bn230128950.fit
The GBM light curve can be found here:
https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2023/bn230128950/quicklook/glg_lc_medres34_bn230128950.gif