TITLE: GCN GRB OBSERVATION REPORT NUMBER: 925 SUBJECT: GRB010126 Optical Observations DATE: 01/01/29 13:14:56 GMT FROM: Holger Pedersen at Copenhagen U Obs H. Pedersen, J. Hjorth, B. L. Jensen (U. of Copenhagen), M. I. Andersen (University of Oulu), J. P. U. Fynbo (ESO, Garching), J. Gorosabel (DSRI, Copenhagen), A. A. Kaas (Nordic Optical Telescope), L. Takalo, and R. Rekola (Tuorla Observatory), report on behalf of a wider collaboration: GRB010126 Optical Observations ------------------------------ "Using the 2.56-m Nordic Optical Telescope (+ALFOSC), La Palma, we have obtained a total of eight images which cover the error box (Hurley, GCN 922) by means of four consecutive pointings: UT Filter Exp.time Seeing =========================================================== 2001 January 27.21 R (4 x ) 180 s 0.85" FWHM 2001 January 28.13 R (4 x ) 180 s 0.90" FWHM Intercomparison of the images has revealed no candidate counterpart to magnitude ~22.5 . The object reported by Bartolini et al. (GCN 924) is detected on two overlapping exposures, i.e. 360 s, at each epoch. Using the nearby USNO star U1350_08031605 as reference, we find R = 21.17 +/- 0.20 (epoch 1) and R = 21.29 +/- 0.20 (epoch 2), i.e. consistent with no variability."