NOTE: uvot_fluxes_wget.pl vrs. 2018-11-07 fem at 190428d03h39m58s718312usUT
NOTE: Source region spec. is: 280.213 +40.322 3"
NOTE: Used archived BAT position of 280.21300  40.32200
NOTE: position reference is GCN_Position_Notice

=========== Draft Upper Limit Circular ========

GRB 190427A: Swift/UVOT Upper Limits

N. P. M. Kuin (UCL-MSSL) and A. Tohuvavohu (PSU)
report on behalf of the Swift/UVOT team:

The Swift/UVOT began settled observations of the field of GRB 190427A
3737 s after the BAT trigger (Tohuvavohu et al., GCN Circ. 24261).
No optical afterglow consistent with the BAT position
*** POSITION REFERENCE is GCN_Position_Notice ***
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 initial exposures are:

Filter         T_start(s)   T_stop(s)      Exp(s)         Mag

u                 3737         3936          197         >19.9

The magnitudes in the table are not corrected for the Galactic extinction
due to the reddening of E(B-V) = 0.06 in the direction of the burst
(Schlegel et al. 1998).