TITLE:   GCN CIRCULAR
NUMBER:  13702
SUBJECT: GRB 120819A: Swift/UVOT Upper Limits
DATE:    12/08/29 21:35:17 GMT
FROM:    Frank Marshall at GSFC  <femarsha@khamseen.gsfc.nasa.gov>

F. E. Marshall (NASA/GSFC) and A. P. Beardmore (U. Leicester)
report on behalf of the Swift/UVOT team:

The Swift/UVOT began settled observations of the field of GRB 120819A
158 s after the BAT trigger (Beardmore et al., GCN Circ. 13681).
No optical afterglow consistent with the optical position
(Malesani et al. GCN Circ. 13683)
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           158          308          147         >21.1
white              158         5439          541         >21.7
v                 4214        22619         1278         >20.9
b                 3598        11864         1164         >21.1
u                 4829        17638         1858         >21.6
w1                4625        16836         1998         >21.4
m2                4418        22980         1629         >21.7
w2                4009        21706         1279         >21.8

The magnitudes in the table are not corrected for the Galactic extinction
due to the reddening of E(B-V) = 0.17 in the direction of the burst
(Schlegel et al. 1998).