GCN Circular 8968
Subject
GRB 090306B: INTEGRAL SPI-ACS light curve
Date
2009-03-10T14:23:05Z (15 years ago)
From
Volker Beckmann at ISDC <Volker.Beckmann@obs.unige.ch>
V. Beckmann, M. Beck, C. Ferrigno, N. Produit, V. Savchenko (ISDC),
J. Borkowski (CAMK/Torun), D. Gotz (CEA/Saclay), S. Mereghetti
(INAF/IASF-Milano), A. von Kienlin (MPE) report on behalf of the
INTEGRAL SPI-ACS GRB team:
GRB 090306B, detected in Swift/BAT slew data (Copete et al. GCN 8944),
has been independently detected by the SPI Anti-Coincidence
System (ACS) on-board INTEGRAL. The SPI-ACS light curve shows the peak
of the burst at 2009-03-06T23:07:21.9 with a maximum count-rate of ~390
counts/50msec. The duration of the GRB is about 14 seconds.
The SPI-ACS light curves are available (both as images and data files)
at http://isdc.unige.ch/Soft/ibas/ibas_acs_web.cgi
The light curves, binned at 50 ms, are derived from 91 independent
detectors with different lower energy thresholds (mainly between 50 keV
and 150 keV) and an upper threshold at about 100 MeV. The ACS response
varies as a function of the GRB incident angle. For these reasons we
caution that the count rates cannot be easily translated into physical
flux units.