TITLE:   GCN CIRCULAR
NUMBER:  15410
SUBJECT: GRB 131030A: D50+BART detection and light curve optical decay
DATE:    13/10/31 01:31:14 GMT
FROM:    Jan Strobl at AI AS CR,Ondrejov  <jan@strobl.cz>

Jan Strobl (1,3), Martin Jelinek (2), Cyril Polasek (1), Michal Jakubec 
(1), Petr Skala (1,3) and Rene Hudec (1,3)
(1. AI ASCR Ondrejov, 2. IAA CSIC Granada, 3. FEE CTU Prague)

We observed the field of the Swift GRB 131030A (Troja et al., GCNC 15402) 
with the 0.5m telescope D50 and 0.25m telescope BART in Ondrejov (Czech 
Republic), starting at 20:57:16 UT, i.e. 56s after the trigger.

The optical afterglow (Virgili et al, GCNC 15406) is clearly detected in 
our images. After an initial peak of about 13.8m (unfiltered, calibrated 
using USNO-B R-band) the lightcurve decays with \alpha~0.9.

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