TITLE: GCN CIRCULAR NUMBER: 5903 SUBJECT: Optical Afterglow observations of GRB 061126 DATE: 06/12/08 21:20:19 GMT FROM: Kuntal Mishra at ARIES,Nainital,India Kuntal Misra (ARIES, Nainital) on behalf of a larger Indian GRB collaboration We observed the optical afterglow detected by SWIFT-UVOT (Vanden Berk et al. GCN 5856) of GRB 061126 (swift trigger=240766, Sbarufatti et al. GCN 5854) in VRI bands using the 1.0-m Sampurnanand Telescope located at ARIES, Nainital on 26 November 2006. Several exposures in VRI bands were taken and the field was calibrated by imaging the Landolt Standard SA 95 region on the same night. The R band magnitude of the afterglow is the following: #Days since burst Magnitude Exposure time 0.41 20.98 ± 0.10 300 0.42 21.04 ± 0.09 900 0.49 21.34 ± 0.10 1800 0.56 21.49 ± 0.10 1800 The observations between 0.41 to 0.56 d gives a power law decay index of ~ 1.4 which is different than the power law index of ~ 1.0 mentioned by Rol et al. (GCN 5876) but consistent with the power law decay index of ~ 1.5 mentioned by Pozanenko et al. (GCN 5902). This message may be cited.