GCN Circular 22617
Subject
GRB 180402A: ISON-NM early optical limits
Event
Date
2018-04-08T20:40:42Z (8 years ago)
From
Alexei Pozanenko at IKI, Moscow <apozanen@iki.rssi.ru>
E. Mazaeva (IKI), L. Elenin (KIAM), A. Pozanenko (IKI), A. Volnova
(IKI), I. Molotov (KIAM) report on behalf of larger GRB follow-up
collaboration:
We observed the field of the Swift short burst GRB 180402A (Lien et
al., GCN 22580) with 0.4-m telescope of ISON-NM observatory starting on
Apr., 02 (UT) 09:45:39, i.e. 40 seconds after the burst trigger. We
obtained 4 unfiltered images of 30 s exposure each. We do not detect any
source within XRT error circle (Lien et al., GCN 22580). Upper limits
are following.
Date start (Ut) t-T0 Exp. UL (3sigma)
(mid.,sec) (s)
2018-04-02 09:45:39 55 1*30 14.5
2018-04-02 09:45:39 133 4*30 15.0
The photometry is based on nearby USNO-B1.0 stars (R2 magnitudes).