GCN Circular 23177
Subject
GRB 180818B: TSHAO optical upper limit
Date
2018-08-26T16:17:39Z (6 years ago)
From
Alexei Pozanenko at IKI, Moscow <apozanen@iki.rssi.ru>
E. Mazaeva (IKI), A. Pozanenko (IKI), A. Kusakin (FAPHI), I. Reva
(FAPHI), A. Volnova (IKI), M. Krugov (FAPHI) report on behalf of larger
GRB follow-up collaboration:
We observed the field of GRB 180818B (Marshall et al., GCN 23149; Veres
et al., GCN 23153) with Zeiss-1000 1-m telescope of Tien Shan
Astronomical Observatory starting on August 08 (UT) 22:20:38. We
obtained several images in R-filter. Within enhanced XRT Swift-XRT
position (Beardmore et al., GCN 23151) we do not detect any object. In
particular we do not detect the afterglow candidate reported in GCN
23161 (Hu et al.) Preliminary photometry of the field is following.
Date UT start t-T0 Filter Exp. OT Err. UL
(mid, days) (s)
2018-08-18 22:20:38 0.42710 R 36*60 n/d n/d 20.4
The photometry is based on several nearby USNO-B1.0 stars.