GRB 240419A: Swift/UVOT Upper Limits

The Swift/UVOT began settled observations of the field of GRB 240419A 113 s after the BAT trigger (Siegel et al., GCN Circ. 36169). No optical afterglow consistent with the enhanced XRT position (Goad et al., GCN Circ. 36174) is detected in the initial UVOT exposures. Preliminary 3-sigma upper limits using the UVOT photometric system (Breeveld et al. 2011, AIP Conf. Proc. 1358, 373) for the first finding chart (FC) exposures and subsequent exposures are: Filter T_start(s) T_stop(s) Exp(s) Mag white_FC 113 263 147 >20.7 u_FC 271 521 246 >20.0 white 113 1025 334 >21.3 v 602 1075 58 >18.6 b 527 721 39 >19.3 u 271 869 285 >20.1 w1 652 845 39 >18.2 m2 627 1099 58 >18.3 w2 578 1050 58 >18.6 The magnitudes in the table are not corrected for the Galactic extinction due to the reddening of E(B-V) = 0.070 in the direction of the burst (Schlegel et al. 1998).