TITLE:   GCN CIRCULAR
NUMBER:  34526
SUBJECT: GRB 230812B: AstroSat LAXPC detection
DATE:    23/08/23 13:46:50 GMT
FROM:    Tilak Katoch at TIFR <tilak@tifr.res.in>

Tilak Katoch, H. M. Antia and Parag Shah TIFR, Mumbai, India.

AstroSat LAXPC data analysis revealed the presence of a strong short GRB 230812B. The GRB burst profile shows that it was triggered at T0 = 18h 58m 08s UT on 12 Aug 2023, when the satellite was in a normal operating mode and well before and after the SAA region.

The lightcurve obtained a burst profile with T90 = 4 sec. The strongest peak measured have a count rate 10678 +/- 105 count/sec in LAXPC10 above the background and 5069 +/- 73 count/sec in LAXPC20 at T0+2 sec.

Both LAXPC instruments (LAXPC10 and LAXPC20) have registered this burst profile in their respective lightcurves. LAXPC20 has a nominal energy range of 3-100 keV, but due to the lower gain in LAXPC10, the energy range is approximately 30-400 keV.

The background subtracted lightcurves of the LAXPC instruments with 0.2 sec time-bin is available at the website:

https://www.tifr.res.in/~astrosat_laxpc/grb230812lc.jpg

LAXPC was built by TIFR in collaboration with the Indian Space Research Organisation. The Indian Space Research Organisation funded, managed and facilitated the project.