GRB 230420A: Swift/UVOT Upper Limits
Abstract
The Swift/UVOT began settled observations of the field of GRB 230420A 99 s after the BAT trigger (Klingler et al., GCN Circ. 33658). No optical afterglow consistent with the XRT position (Osborne et al., GCN Circ. 33661) 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) exposure and subsequent exposures are: Filter T_start(s) T_stop(s) Exp(s) Mag white_FC 99 249 147 >21.1 u_FC 258 508 246 >20.5 white 99 1190 353 >21.7 v 590 4885 255 >19.5 b 514 1165 58 >19.9 u 258 1141 285 >20.6 w1 814 5109 52 >19.1 w2 4481 4681 197 >19.8 The magnitudes in the table are not corrected for the Galactic extinction due to the reddening of E(B-V) = 0.017 in the direction of the burst (Schlegel et al. 1998).
- Publication:
-
GRB Coordinates Network
- Pub Date:
- April 2023
- Bibcode:
- 2023GCN.33673....1O