[vsnet-grb-info 16924] GRB 150818A: possible SN rise in light curve of Mondy observations

[GCN Circulars]

TITLE:   GCN CIRCULAR
NUMBER:  18205
SUBJECT: GRB 150818A: possible SN rise in light curve of Mondy observations
DATE:    15/08/27 16:54:50 GMT
FROM:    Alexei Pozanenko at IKI, Moscow  <apozanen at iki.rssi.ru>

E. Mazaeva (IKI), E. Klunko (ISTP), A. Volnova (IKI), I. Korobtsev 
(ISTP), A. Pozanenko (IKI) report on behalf of larger GRB follow-up 
collaboration:

We continue observations of the Swift GRB 150818A (D'Elia et al., GCN 
18152) with AZT-33IK telescope of Sayan observatory (Mondy).   We 
imaged optical transient (Marshall et al., GCN 18155; McCauley et al., 
GCN 18161; Schulze et al., GCN 18164; Mazaeva et al., GCN 18175)  in 
R-filter on Aug., 21, 22, 23, and 26.  The optical transient is clearly 
visible in each epochs. Preliminary light curve of the optical transient 
can be found in

http://grb.rssi.ru/GRB150818A/GRB150818A_R_lc.png

(Photometry is based on USNO-B1.0 stars referenced in (Mazaeva et al., 
GCN 18175).

One can suggest that steady re-brightening of the optical transient is 
related to a Supernova associated with nearby GRB 150818A  (z = 0.282, 
Sanchez-Ramirez et al., GCN 18177). We encourage observation for 
spectroscopic SN-confirmation.