GCN Circular 1204
GRB 011211: Evidence for an Optical Break S. Holland (Notre Dame), P. Berlind, D. Bersier, S. Jha, K. Z. Stanek (Harvard-Smithsonian Center for Astrophysics), I. Soszynski (Warsaw University Observatory), P. M. Garnavich (Notre Dame) report: We have obtained deep VRI images of the field containing GRB 011211 using the 1.2-meter telescope with the 4Shooter at the Fred Lawrence Whipple Observatory on Dec. 14.5 UT. The optical afterglow of GRB 011211 is not visible on any of our images. The predicted magnitudes, based on the power-law fits of Soszynski et al. (2001, GCN 1199), and the estimated limiting magnitudes of our images are give below. Filter Predicted Limiting Magnitude V 22.10 22.3 +/- 0.2 R 21.99 22.4 +/- 0.2 I 21.25 21.0 +/- 0.2 These magnitudes are relative to the VRI magnitudes for USNO star U0675_11427359 given by Henden (2001, GCN 1197). Our non-detection suggests that there has been a break in the light curve of the optical afterglow of GRB 011211. The break occurred between 1.5 and 2.7 days after the burst (between Dec. 13.3 and Dec. 14.5). The R-band limiting magnitude suggests that the slope after the break is at least -1.4. The V- and I-band limiting magnitudes are consistent with no break. This message may be cited.