GCN Circular 27128
Subject
GRB 200216B: second epoch optical upper limit at Mondy observatory
Event
Date
2020-02-19T12:01:00Z (6 years ago)
From
Alexei Pozanenko at IKI, Moscow <apozanen@iki.rssi.ru>
S. Belkin (IKI), A. Pozanenko (IKI), E. Klunko (ISTP), E. Mazaeva (IKI),
A. Volnova (IKI) report on behalf of IKI-GRB-FuN:
We observed the field of GRB 200216B (D'Avanzo et al., GCN 27102: Fermi
GBM team, GCN 27101) with AZT-33IK telescope of Sayan observatory
(Mondy) starting on Feb. 18 (UT) 16:02:31. We did not detect any object
in the enhanced Swift-XRT position (Goad et al., GCN 27106). In
particular we do not detect possible IR-counterpart (Levan et al., GCN
27114). Upper limit is 22.8R.
We detected the object reported earlier (Pozanenko et al., GCN 27122)
with coordinates (J2000) 10:41:44.54 +19:28:19.3 which is 14.5 arcsec
apart from center of enhanced XRT error circle (Goad et al., GCN 27106).
Preliminary photometry of the object is following:
Date UT start t-T0 Filter Exp. OT Err. UL(3sigma)
(mid, days) (s)
2020-02-18 16:02:31 2.12497 R 30*120 22.7 0.3 22.8
Power law index of a light curve of the object calculated between the
two epochs is about -0.3. Therefore the object might not be related to
GRB 200216B.