GCN Circular 23206
Subject
GRB 180904A: AbAO optical upper limit
Date
2018-09-05T16:18:22Z (6 years ago)
From
Alexei Pozanenko at IKI, Moscow <apozanen@iki.rssi.ru>
A. Volnova (IKI), A. Pozanenko (IKI), R. Inasaridze (AbAO), E.
Mazaeva (IKI), V. Ayvazian (AbAO), O. Kvaratskhelia (AbAO), G.
Kapanadze (AbAO), I. Molotov (KIAM) report on behalf of larger GRB
follow-up collaboration:
We observed the field of the Swift GRB 180904A (D'Ai et al., GCN 23194)
with AS-32 (0.7m) telescope of Abastumani Observatory starting on
September 04 (UT) 21:52:23. We do not detect any object within
enhanced XRT position (Osborne et al., GCN 23196). Preliminary
photometry of the field is following:
Date UT start t-T0 Filter Exp. OT Err. UL
(mid, days) (s)
2018-09-04 21:52:23 0.05731 CR 70*60 n/d n/d 21.5
The photometry is based on nearby USNO-B1.0 stars (R2 magnitude)
USNO-B.1_id R2
1366-0296056 14.72
1366-0296068 15.43
1365-0287325 15.62
1366-0296106 15.21
1366-0296088 14.95
1366-0296093 14.37