GRB 230101A
GCN Circular 33141
Subject
GRB 230101A: AstroSat CZTI detection
Date
2023-01-03T10:56:14Z (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 GRB 230101A which was
also detected by Fermi GBM (GCN Circ. 33130).
The source was clearly detected in the 20-200 keV energy range. The
light curve showed multiple peaks of emission with the strongest peak at
2023-01-01 02:16:48.5 UTC. The measured peak count rate associated with
the burst is 183 (+18, -16) counts/s above the background in the
combined data of all quadrants, with a total of 4974 (+674, -726)
counts. The local mean background count rate was 435 (+1, -1) counts/s.
Using cumulative rates, we measure a T90 of 81 (+12, -27) s.
It was also clearly detected in the CsI anticoincidence (Veto) detector
in the 100-500 keV energy range. The light curve peaks at 2023-01-01
02:16:42.7 UTC. The measured peak count rate is 830 (+65, -61) counts/s
above the background in the combined Veto data of all quadrants, with a
total of 14726 (+2045, -2365) counts. The local mean background count
rate was 7515 (+5, -5) counts/s. We measure a T90 of 27 (+17, -8) 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 33130
Subject
GRB 230101A: Fermi GBM Final Real-time Localization
Date
2023-01-01T02:26:46Z (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 02:16:38 UT on 1 Jan 2023, the Fermi Gamma-ray Burst Monitor (GBM) triggered and located GRB 230101A (trigger 694232203.998664 / 230101095).
The on-ground calculated location, using the Fermi GBM trigger data, is RA = 206.3, Dec = -21.9 (J2000 degrees, equivalent to J2000 13h 45m, -21d 53'), with a statistical uncertainty of 2.8 degrees.
The angle from the Fermi LAT boresight is 49.0 degrees.
The skymap can be found here:
https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2023/bn230101095/quicklook/glg_skymap_all_bn230101095.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/bn230101095/quicklook/glg_healpix_all_bn230101095.fit
The GBM light curve can be found here:
https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2023/bn230101095/quicklook/glg_lc_medres34_bn230101095.gif