NOTE: uvot_fluxes_wget.pl vrs. 2018-11-07 fem at 200818d01h06m58s904365usUT
NOTE: Source region spec. is: 154.131 -33.921 3"
NOTE: Used archived BAT position of 154.13100 -33.92100
NOTE: position reference is GCN_Position_Notice

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

GRB 200817: Swift/UVOT Upper Limits

A. A. Breeveld (UCL-MSSL) and ***BA*** (***BA INSTITUTION***)
report on behalf of the Swift/UVOT team:

The Swift/UVOT began settled observations of the field of GRB 200817
88 s after the BAT trigger (***Author*** et al., GCN Circ. ????).
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 first
finding chart (FC) exposure and subsequent exposures are:

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

white_FC            88          237          147         >20.2
u_FC               299          549          246         >19.6
white               88         1721          410         >20.7
v                  629         1770          136         >18.5
b                  555         1696          117         >19.4
u                  299         1671          343         >19.8
w1                 678         1647          117         >18.8
m2                 653         1783          124         >19.2
w2                 605         1746          136         >19.0

The magnitudes in the table are not corrected for the Galactic extinction
due to the reddening of E(B-V) = 0.10 in the direction of the burst
(Schlegel et al. 1998).