GCN Circular 16812
GRB 140909A: Swift/UVOT Upper Limits M. H. Siegel (PSU) and E. Sonbas (Adiyaman Univ.) report on behalf of the Swift/UVOT team: The Swift/UVOT began settled observations of the field of GRB 140909A 44028 s after the BAT trigger (Palmer et al., GCN Circ. 16808). No optical afterglow consistent with the XRT position (Pagani et al. GCN Circ. 16811) is detected in the initial UVOT exposure. The preliminary 3-sigma upper limit using the UVOT photometric system (Breeveld et al. 2011, AIP Conf. Proc. 1358, 373) for the initial exposure is: Filter T_start(s) T_stop(s) Exp(s) Mag white 44028 56310 3213 >22.0 The magnitude is not corrected for the Galactic extinction due to the reddening of E(B-V) = 0.015 in the direction of the burst (Schlegel et al. 1998).