TITLE:   GCN CIRCULAR
NUMBER:  16272
SUBJECT: GRB 140423A: HCT optical observations
DATE:    14/05/15 16:31:36 GMT
FROM:    D.K. Sahu at Indian Inst of Astrophysics,Bangalore  <dks@iiap.res.in>

D.K. Sahu (Indian Institute of Astrophysics, Bangalore, India) reports:

The optical afterglow of Swift detected GRB 140423A (E.Sonbas et al., 
GCN 16142) was observed in Bessell R band, with the 2m. Himalayan 
Chandra Telescope of the Indian Astronomical Observatory, Hanle, India. 
Observations were made between 15:12 UT and 20:48 UT on 23/04/2014.
The optical afterglow (Elenin et al., GCN 16143; Kaur et al., 
GCN 16144; Ferrante et al., GCN 16145) was detected in our 
individual frames. The preliminary R magnitudes of the optical 
afterglow calibrated using nearby USNO B1 stars is as under.

Date Mid UT Exp R Magnitude
(sec) 
23-04-2014 15:03 180+300 20.35 +/- 0.05 
23-04-2014 17:44 2x300 20.68 +/- 0.06 
23-04-2014 20.40 2x300 21.08 +/- 0.06