[vsnet-grb-info 17180] GRB 151029A: LCOGT-FTS afterglow observations

[GCN Circulars]

TITLE:   GCN CIRCULAR
NUMBER:  18530
SUBJECT: GRB 151029A: LCOGT-FTS afterglow observations
DATE:    15/10/29 15:42:47 GMT
FROM:    Cristiano Guidorzi at Ferrara U,Italy  <guidorzi at fe.infn.it>

S. Dichiara (U. Ferrara, ICRANet), C. Guidorzi (U. Ferrara), S. 
Kobayashi (LJMU), A. Gomboc (U. Ljubljana) on behalf of a larger 
collaboration report:

The 2-m LCOGT Faulkes Telescope South began observing Swift GRB 151029A 
(Ukwatta et al. GCN 18522) on October 29, 09:33 UT (1.7 hours after the 
burst trigger) with SDSS R and I filters. We marginally detect the 
optical afterglow (Ukwatta et al. GCN 18522; Knust et al. GCN 18523; 
Tanvir et al. GCN 18524) due to poor sky conditions with the following 
magnitudes:

Mid Time      Exposure       Filter       Magnitude
(hours)           (s)
-------------------------------------------------------
1.8            5x120         R           20.6 +- 0.4
2.0            5x120         I           21.0 +- 0.5
-------------------------------------------------------

Calibration is done against nearby USNOB-1 star RA(J2000)=02:34:10.069, 
DEC(J2000)=-35:24:13.54, assuming R2=16.95 mag and I=17.63 mag.