TITLE:   GCN CIRCULAR
NUMBER:  32371
SUBJECT: GRB 220711B: Swift/UVOT Upper Limits
DATE:    22/07/12 05:02:33 GMT
FROM:    Noel Klingler at NASA-GSFC / UMBC  <njk5441@psu.edu>

N. J. Klingler (GSFC/UMBC/CRESTII) and A. D'Ai (INAF-IASFPA)
report on behalf of the Swift/UVOT team:

The Swift/UVOT began settled observations of the field of GRB 220711B
114 s after the BAT trigger (D'Ai et al., GCN Circ. 32366).
No optical afterglow consistent with the XRT position
(Beardmore et al. GCN Circ. 32370)
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           114          264          147         >21.0
u_FC               326          576          246         >20.2
white              114          915          221         >21.0
v                  655         4601          236         >19.7
b                  581          773           39         >19.7
u                  326         5120          368         >20.4
w1                 704         5011          216         >20.5
m2                 852         4806          216         >19.4
w2                 631         4396          216         >20.4

The magnitudes in the table are not corrected for the Galactic extinction
due to the reddening of E(B-V) = 0.067 in the direction of the burst
(Schlegel et al. 1998).