[vsnet-grb-info 14267] GRB 131205A: Swift/UVOT Upper Limits

[GCN Circulars]

TITLE:   GCN CIRCULAR
NUMBER:  15581
SUBJECT: GRB 131205A: Swift/UVOT Upper Limits
DATE:    13/12/05 17:40:58 GMT
FROM:    Craig Swenson at PSU/Swift  <cswenson at astro.psu.edu>

C. A. Swenson (PSU) and T. N. Ukwatta (MSU)
report on behalf of the Swift/UVOT team:

The Swift/UVOT began settled observations of the field of GRB 131205A
94 s after the BAT trigger (Ukwatta et al., GCN Circ. 15578).
No optical afterglow consistent with the enhanced XRT position
(Beardmore et al. GCN Circ. 15580) is detected in the initial UVOT
exposures.  Because the spacecraft attitude was not stable during
the first finding chart exposure, we do not report on that exposure here.

Preliminary 3-sigma upper limits using the UVOT photometric system
(Breeveld et al. 2011, AIP Conf. Proc. 1358, 373) for the second
finding chart (FC) exposure and subsequent exposures are:

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

u_FC               306          556          246 >20.8
white              586        12884         1171 >21.7
v                  636         6778          471 >20.5
b                  561        12313         1160 >21.5
u                  306        11400         1386 >22.0
w1                 685         7121          385 >20.4
m2                 660         6983          471 >20.4
w2                 611         6574          471 >20.6

The magnitudes in the table are not corrected for the Galactic extinction
due to the reddening of E(B-V) = 0.26 in the direction of the burst
(Schlegel et al. 1998).