NOTE: uvot_fluxes_wget.pl vrs. 2020-11-03a fem at 210325d02h00m40s955806usUT
NOTE: Source region spec. is: 259.664 15.677 3"
NOTE: Used archived BAT position of 259.66400  15.67700
NOTE: position reference is GCN_Circ-29701
WARNING: t_start for light curve (103622) and t_start from the exposure report (0) do not agree.
  Replace ??? in draft Circular with correct value.

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

GRB 210323B: 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 210323B
***???*** s after the BAT trigger (***Author*** et al., GCN Circ. ????).
No optical afterglow consistent with the BAT position
*** POSITION REFERENCE is GCN_Circ-29701 ***
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

white           104205       110494         1154         >21.7
v               104787       111030         1084         >19.6
u               103622       109891         1154         >20.9

The magnitudes in the table are not corrected for the Galactic extinction
due to the reddening of E(B-V) = 0.081 in the direction of the burst
(Schlegel et al. 1998).