GCN Circular 21206
Subject
GRB 170519A: Mondy optical observations
Event
Date
2017-06-05T19:07:17Z (9 years ago)
From
Alexei Pozanenko at IKI, Moscow <apozanen@iki.rssi.ru>
E. Mazaeva (IKI), A. Pozanenko (IKI), E. Klunko (ISTP), A. Volnova (IKI)
report on behalf of larger GRB follow-up collaboration:
We observed the field of GRB 170519A (Ukwatta et al., GCN 21106) with
AZT-33IK telescope of Sayan observatory (Mondy) starting on May 20 (UT)
16:27:01. We took several images in R-filter with exposures of 120 s.
The optical afterglow (Ukwatta et al., GCN 21106; Izzo, et al., GCN
21108) is clearly visible in single images.
We continued our observations on May 27 (UT) 16:28:02, i.e., ~8.5 days
after the BAT trigger. We took several R-filtered images. We do not
detect the optical counterpart in the enhanced XRT error circle
(Beardmore et al., GCN 21107).
Preliminary photometry of the afterglow is following:
Date UT start t-T0 Filter Exp. OT Err. UL
(mid, days) (s)
(3 sigma)
2017-05-20 16:27:01 1.47708 R 10*120 19.99 0.03 22.8
2017-05-20 17:07:02 1.50487 R 10*120 19.99 0.03 22.6
2017-05-27 16:28:02 8.49905 R 39*120 n/d n/d 22.6
The photometry is based on nearby SDSS stars reported by
Mazaeva et al. (GCN 21169).