TITLE: GCN CIRCULAR NUMBER: 11196 SUBJECT: GRB 100902A: 1.5m OSN I-band Upper Limits DATE: 10/09/03 18:31:15 GMT FROM: Rubén Sánchez-Ramírez at IAA-CSIC J.C. Tello, R. Sánchez-Ramírez, A. Sota, J. Gorosabel, A.J. Castro-Tirado (IAA-CSIC, Granada), report on behalf of a larger collaboration: "We have carried out I-band observations of the Swift GRB 100902A (Sakamoto et al. GCNC 11181) on Sep 3.1076 - 3.1492 UT (~7.05 hr after the onset of the burst, mean observing time) with the 1.5m telescope at Observatorio de Sierra Nevada, Spain. We do not detect any optical source within the SWIFT/XRT error circle (Beardmore et al. GCNC 11188). The 3 sigma limiting magnitude of the co-added I-band image (Texp=16x200s) is I ~ 21.8, calibrated against the USNO B1.0 catalogue."