NOTE: uvot_fluxes_wget.pl vrs. 2020-11-03a fem at 220501d02h43m17s624395usUT
NOTE: Source region spec. is: 97.61217 9.54753 4"
NOTE: Used archived XRT position of  97.61217   9.54753  4.00
NOTE: position reference is GCN_Circulars-31973

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

GRB 220430A: Swift/UVOT Upper Limits

M. A. Baer (PSU) and Ambrosi (INAF-IASFPA)
report on behalf of the Swift/UVOT team:

The Swift/UVOT began settled observations of the field of GRB 220430A
37 s after the BAT trigger (Ambrosi et al., GCN Circ. 31972).
No optical afterglow consistent with the XRT position
(Osborne et al. GCN Circ. 31973)
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            60          210          147         >20.3
u_FC               272          522          246         >19.8
white               60          938          245         >20.6
v                   37         4498          126         >18.4
b                  528          721           39         >19.0
u                  272          870          285         >19.9
w1                 651          845           39         >18.8
m2                 627          646           19         >18.3
w2                 578         4415          216         >20.4

The magnitudes in the table are not corrected for the Galactic extinction
due to the reddening of E(B-V) = 0.649 in the direction of the burst
(Schlegel et al. 1998).