GCN Circular 13883

Subject

GRB 121017A: Swift/UVOT Upper Limits

Event

Date

2012-10-18T11:31:14Z (14 years ago)

From

Alice Breeveld at MSSL-UCL <aab@mssl.ucl.ac.uk>

A. A. Breeveld (MSSL-UCL) and D. Grupe (PSU) report on behalf of the 
Swift/UVOT team:

The Swift/UVOT began settled observations of the field of GRB 121017A 
1142 s after the BAT trigger (Grupe et al., GCN Circ. 13875Loading...
 
 ).
No optical afterglow consistent with the XRT position (Goad et al. GCN 
Circ. 13879Loading...
 
 ) 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          1142         1291          147         >21.1
white             1142         1442          167         >21.2
v                 1298         1492           39         >18.5
b                 1397         1417           19         >19.1
u                 1373         1392           19         >18.6
w1                1347         1367           19         >18.1
w2                1448         1468           19         >18.1

The magnitudes in the table are not corrected for the Galactic 
extinction due to the reddening of E(B-V) = 0.44 in the direction of the 
burst (Schlegel et al. 1998).