NOTE: uvot_fluxes_wget.pl vrs. 2018-01-16 fem at 180510d22h52m32s479758usUT
NOTE: Source region spec. is: 276.33029 -31.90689 4"
NOTE: Used archived XRT position of 276.33029 -31.90689  4.00
NOTE: position reference is GCN_Circulars-22695

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

GRB 180510A: Swift/UVOT Upper Limits

S. R. Oates (U.Warwick) and J. D. Gropp (PSU)
report on behalf of the Swift/UVOT team:

The Swift/UVOT began settled observations of the field of GRB 180510A
97 s after the BAT trigger (Gropp et al., GCN Circ. 22695).
No optical afterglow consistent with the XRT position
(Gropp et al. GCN Circ. 22695)
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            97          247          147         >20.9
white               97          247          147         >20.9
u                  310          322           12         >17.1

The magnitudes in the table are not corrected for the Galactic extinction
due to the reddening of E(B-V) = 0.26 in the direction of the burst
(Schlegel et al. 1998).