NOTE: uvot_fluxes_wget.pl vrs. 2023-03-23 fem at 240305d04h09m59s458926usUT
NOTE: Source region spec. is: 229.7358 -57.3617 4"
NOTE: Used archived XRT position of 229.73580 -57.36170  4.00
NOTE: position reference is GCN_Notice

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

GRB 240304: Swift/UVOT Upper Limits

M. H. Siegel (PSU) and ***BA*** (***BA INSTITUTION***)
report on behalf of the Swift/UVOT team:

The Swift/UVOT began settled observations of the field of GRB 240304
195 s after the BAT trigger (***Author*** et al., GCN Circ. ????).
No optical afterglow consistent with the XRT position
*** POSITION REFERENCE is GCN_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 first
finding chart (FC) exposure and subsequent exposures are:

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

u_FC               195          445          246         >20.2
v                  503         1849          175         >18.9
b                  452         1798          175         >20.4
u                  195         1923          510         >21.0
w1                 552         1898          175         >20.0
m2                 527         1724          136         >20.1
w2                 478         1824          136         >20.6

The magnitudes in the table are not corrected for the Galactic extinction
due to the reddening of E(B-V) = 8.227 in the direction of the burst
(Schlegel et al. 1998).