GCN Circular 1193
Fading of the optical source associated of XRF 011211 J. S. Bloom and Edo Berger report on behalf of the larger Caltech-NRAO-CARA GRB Collaboration: "Following the report of a new bright source (Grav et al. GCN #1191) in the field of XRF 011211 (Gandolfi et al. GCN #1188, GCN #1189; Santos-Lleo et al. GCN #1192) we began observing the source position with the Palomar 200" + JCAM dual-band optical imager on 12 Dec 01, 10:48 UT in very poor observing conditions. In Sloan-r', the source is clearly fainter than the three objects to the northwest (the source plus the three objects appear to be of comparable brightness on the Grav et al. finding chart). This confirms the transient nature of the source discovered by Grav et al. and helps solidify its association with XRF 011211. The source was also detected the Sloan g' filter, suggesting an origin z <~ 4.3. A finding chart with a single g' and r' integration (110s and 100s exposure) may be found at: http://www.astro.caltech.edu/~jsb/xrf011211.gif This message may be cited.