TITLE: GCN CIRCULAR NUMBER: 35296 SUBJECT: GRB231115A: TURBO Pre-Burst Optical Upper Limits DATE: 23/12/06 21:42:43 GMT FROM: Robert Strausbaugh at Eastern Illinois University R. Strausbaugh (Eastern Illinois University), Daniel Warshofsky (UMN), Pat Kelly (UMN), Mandeep S. S. Gill (UMN), Alexandre Toscano (UMN), Yilin Lu(UMN), Sydney Leggio (UMN), Aksinya Kamenshikova (UMN) report on behalf of a larger collaboration: We observed M82, including the localization region for the Fermi GRB 231115A (Fermi GBM team, GCN 35035), with the Total-Coverage Ultrafast Response to Binary-Mergers Observatory (TURBO) prototype telescope in St. Paul, Minnesota, USA, as part of a high-cadence ongoing survey for transients in nearby galaxies. We visited the field 55 times on November 15 UT, with the last visit occurring at 9:06 UT in SDSS r and g bands respectively (corresponding to 6.5 hours before the GRB trigger time). Each exposure is 30 seconds. We do not detect a source at the same location as the GROWTH-India counterpart (Kumar et al., GCN 35041) in either band. The 3-sigma upper limits in the table below are calculated using the Pan-STARRS catalog as reference, and are not corrected for Galactic extinction. The TURBO prototype in St. Paul consists of two co-mounted 11-inch telescopes each with a 6.6 square degree field of view. TURBO, which is under construction, will consist of two arrays of 8 pairs of co-mounted 11-inch telescopes at two dark-sky sites: Magdalena Ridge Observatory, New Mexico, USA and Skinakas Observatory, Crete, Greece. mjd g upper limit (AB) r upper limit (AB) 60262.97035880 - 16.0 60262.97244213 16.9 - 60263.00063657408 - 15.9 60263.00407407407 - 15.7 60263.007106481484 - 16.1 60263.012094907404 - 15.6 60263.015555555554 - 15.9 60263.01940972222 - 16.0 60263.02327546296 - 15.9 60263.02715277778 - 16.3 60263.03057870371 - 16.1 60263.034212962964 - 16.1 60263.03765046296 - 16.4 60263.04111111111 - 15.7 60263.04293981481 - 15.8 60263.04591435185 16.5 15.7 60263.04896990741 - 16.4 60263.05202546297 16.5 15.8 60263.055 16.5 15.6 60263.058020833334 - 15.8 60263.061006944445 - 16.0 60263.06407407407 - 15.9 60263.070497685185 - 16.3 60263.07403935185 - 16.2 60263.07748842592 - 15.8 60263.080462962964 - 16.3 60263.08472222222 - 16.1 60263.087592592594 16.5 16.4 60263.09365740741 16.4 16.3 60263.09645833333 15.9 16.5 60263.099375 - 16.4 60263.1171412037 - 16.7 60263.120150462964 16.3 16.3 60263.12315972222 - 15.4 60263.14434027778 16.6 15.6 60263.14716435185 16.0 15.7 60263.15039351852 15.7 16.1 60263.15372685185 16.5 16.0 60263.156539351854 15.8 16.0 60263.159421296295 16.0 16.3 60263.162314814814 16.6 15.8 60263.165138888886 15.8 16.8 60263.16957175926 16.3 16.2 60263.172997685186 16.4 - 60263.176516203705 16.5 16.5 60263.19818287037 16.8 15.8 60263.21885416667 16.9 16.8 60263.22230324074 17.4 17.0 60263.24633101852 17.3 16.4 60263.268900462965 17.3 16.6 60263.27537037037 16.9 16.9 60263.27885416667 17.3 17.0 60263.283229166664 17.0 16.9 60263.28666666667 16.9 17.0 60263.29603009259 17.4 16.8