TITLE: GCN CIRCULAR NUMBER: 6199 SUBJECT: GRB 070311: MDM Optical Follow-up DATE: 07/03/12 16:59:07 GMT FROM: Jules Halpern at Columbia U. J. P. Halpern & E. Armstrong (Columbia U.) report on behalf of the MDM Observatory GRB follow-up team. "We observed the afterglow of INTEGRAL GRB 070311 in the R band for a second night using the MDM 1.3m telescope. A combined 8x600 s image with mid-epoch Mar. 12 03:33 UT yields R = 23.05 +/- 0.10 using the same comparison star as in GCN 6195. The corresponding power-law decay index is -0.53 between 0.9 and 25.7 hours. The seeing was ~1.7". There is possible evidence for emission extending ~1.5" to the west of the OT. If so, it may contribute to the shallow decay index. MDM images are posted at http://www.astro.columbia.edu/~jules/grb/070311/ This message may be cited"