GCN Circular 16494

A. A. Breeveld (UCL-MSSL) and A. Y. Lien (GSFC/UMBC) report on behalf of 
the Swift/UVOT team:

The Swift/UVOT began settled observations of the field of GRB 140629A 
101 s after the BAT trigger (Lien et al., GCN Circ. 16477
Not found
 
 
).
A fading source consistent with the XRT position (Evans et al. GCN Circ. 
16479
Not found
 
 
) is detected in the initial UVOT exposures. The fact that it is 
not seen in uvm2 or uvw2 filters is consistent with the redshift given 
by Moskvitin et al., GCN Circ. 16489
Not found
 
 
 and D�Avanzo et al., GCN Circ. 16493
Not found
 
 
.

The preliminary UVOT position is:
     RA  (J2000) =  16:35:54.42 = 248.97676 (deg.)
     Dec (J2000) = +41:52:36.8  =  41.87690 (deg.)
with an estimated uncertainty of 0.42 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              101          251          147         14.78 � 0.02
v                  643          663           20         15.29 � 0.09
b                  569          589           20         15.70 � 0.06
u                  313          563          246         14.89 � 0.03
w1                 692          712           19         17.5  � 0.3
m2                 667          687           19        >17.5
w2                 619          639           19        >18.0

The magnitudes in the table are not corrected for the Galactic 
extinction due to the reddening of E(B-V) = 0.01 in the direction of the 
burst (Schlegel et al. 1998).