NOTE: uvot_fluxes_wget.pl vrs. 2018-11-07 fem at 200425d00h58m49s954508usUT
NOTE: Source region spec. is: 307.5056 -39.6937 3"
NOTE: Used archived BAT position of 307.50560 -39.69370
NOTE: position reference is GCN_FOM_Notice

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

GRB 200424: Swift/UVOT Upper Limits

***UBS*** (***INSTITUTION***) and ***BA*** (***BA INSTITUTION***)
report on behalf of the Swift/UVOT team:

The Swift/UVOT began settled observations of the field of GRB 200424
17043 s after the INTEGRAL trigger (***Author*** et al., GCN Circ. ????).
No optical afterglow consistent with the INTEGRAL position
*** POSITION REFERENCE is GCN_FOM_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

v                17701        30161          236         >19.1
b                17291        29752          236         >20.3
u                17207        29667          236         >20.0
w1               17043        29583          492         >20.0
m2               17784        30616         2678         >20.9
w2               17376        30077          944         >20.5

The magnitudes in the table are not corrected for the Galactic extinction
due to the reddening of E(B-V) = 0.05 in the direction of the burst
(Schlegel et al. 1998).