NOTE: uvot_fluxes_wget.pl vrs. 2023-03-23 fem at 230907d22h22m22s887057usUT
NOTE: Source region spec. is: 79.757 -47.887 3"
NOTE: Used archived BAT position of  79.75700 -47.88700
NOTE: position reference is GCN_Circ-34637

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

GRB 230906A: 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 230906A
93270 s after the BAT trigger (***Author*** et al., GCN Circ. ????).
No optical afterglow consistent with the BAT position
*** POSITION REFERENCE is GCN_Circ-34637 ***
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            93270       104693         3382         >22.5

The magnitudes in the table are not corrected for the Galactic extinction
due to the reddening of E(B-V) = 0.023 in the direction of the burst
(Schlegel et al. 1998).