TITLE:   GCN CIRCULAR
NUMBER:  23964
SUBJECT: GRB 190311A: Mondy optical observations
DATE:    19/03/13 15:51:30 GMT
FROM:    Elena Mazaeva at IKI, Moscow  <30.v@mail.ru>

E. Mazaeva (IKI), E. Klunko (ISTP), A. Pozanenko (IKI), S. Belkin (IKI), A. Volnova (IKI) report on behalf of IKI-GRB-FuN:

We continue observations the afterglow of GRB 190311A (Troja et al. GCN 23946) with AZT-33IK telescope of Sayan observatory (Mondy) starting on Mar. 12 (UT) 16:23:42. Preliminary photometry of the afterglow detected previously (Troja et al. GCN 23946; Pozanenko et al. GCN 23947; Zhu et al. GCN 23948; Gorbovskoy et al. GCN 23949; Belkin et al. GCN 23951; Mao et al. GCN 23954; Mazaeva et al. GCN 23958; Selsing et al. GCN 23962; Blazek et al. GCN 23963) is following.

Date       UT start t-T0    Filter  Exp. OT    Err.  UL
                     (mid, days)     (s)

2019-03-12 16:23:42 1.11471  R  5400 22.16 0.09  23.5

The photometry is based on several nearby SDSS-DR12 stars used in GCN 23958.