GCN Circular 13461

S. R. Oates (MSSL-UCL) and M. J. Page (MSSL-UCL)
report on behalf of the Swift/UVOT team:

The Swift/UVOT began settled observations of the field of GRB 120712A
95 s after the BAT trigger (Page et al., GCN Circ. 13454
Not found
 
 
).
A source consistent with the XRT position (Osborne et al., GCN Circ. 13456
Not found
 
 
) 
and the optical position reported by GROND (Elliott et al., GCN Circ. 13457
Not found
 
 
) 
is detected in the initial UVOT exposures.

The preliminary UVOT position is:
  RA  (J2000) =  11:18:21.25 = 169.58854 (deg.)
  Dec (J2000) = -20:02:01.7  = -20.03380 (deg.)
with an estimated uncertainty of 0.50 arc sec. (radius, 90% confidence).

Preliminary detections and 3-sigma upper limits using the UVOT photometric system
(Breeveld et al. 2011, AIP Conf. Proc. 1358, 373) for the early exposures are: 

Filter         T_start(s)   T_stop(s)      Exp(s)           Mag

white (FC)         95           245          147        16.95 +/- 0.03
white              861         1010          150        18.93 +/- 0.09
v                  637          657           19        16.79 +/- 0.15
b                  563        18691         1160        >21.8
u                  308        35517         2569        >22.1
w1                 686        35216         3108        >22.0
m2                4818        41481         3296        >22.1
w2                 613        40167         2931        >22.1

The magnitudes in the table are not corrected for the Galactic extinction
due to the reddening of E(B-V) = 0.04 in the direction of the burst
(Schlegel et al. 1998).