GCN Circular 17110
Subject
GRB 141121A: SPI-ACS/INTEGRAL observations
Event
Date
2014-11-28T18:10:04Z (11 years ago)
From
Alexei Pozanenko at IKI, Moscow <apozanen@iki.rssi.ru>
A. Pozanenko (IKI), P. Minaev (IKI), V. Vybornov (IKI), A. Volnova
(IKI), E. Mazaeva (IKI) report:
We inspected the SPI-ACS data of INTEGRAL observatory covering trigger
time of the Swift GRB 141121A (Lien et al., GCN 17075) and MAXI/GSC
(Honda et al., GCN 17077). At the BAT/Swift trigger time of the GRB
141121A (UT) T0=03:50:43 we do not found any significant emission above
background in SPI-ACS data in different time scales (0.05 s, 5 s, and 50
s). We also do not find any activity at the second BAT episode (T0+550
s to T0+675 s).
At the time of about T0-800 s we found in SPI-ACS data the activity
corresponding to the first Konus-Wind episode (Golenetskii et al., GCN
17108). The duration of the activity is about 200 s and clearly visible
in SPI-ACS light curve. The start time of the maximal count rate of
SPI-ACS light curve (binning with 50 s bin duration) is T0-725 s. In
both cases TO and T0-725 s the boresight of SPI-ACS is the same and
equal to 119 degrees. If this episode is related to the GRB 141121A and
taking into account SPI-ACS energy threshold (>~ 80 keV) one can suggest
the this episode of GRB 141121A is harder than main activity detected by
BAT/Swift.
We do not detect any significant activity at the time of the MAXI/GSC
detection (Honda et al., GCN 17077).
The SPI-ACS light curves can be found at
http://grb.rssi.ru/GRB141121A/grb141121_spi-acs_50sec.png
http://grb.rssi.ru/GRB141121A/grb141121_spi-acs_5sec.png