[vsnet-grb-info 12929] GRB 130305A: Swift/UVOT Upper Limit

[GCN Circulars]

TITLE:   GCN CIRCULAR
NUMBER:  14268
SUBJECT: GRB 130305A: Swift/UVOT Upper Limit
DATE:    13/03/07 12:34:13 GMT
FROM:    Alice Breeveld at MSSL-UCL  <a.breeveld at ucl.ac.uk>

A. A. Breeveld (MSSL-UCL), Daniele Malesani (DARK/NBI), Bin-Bin Zhang 
(PSU), S. R. Oates (MSSL-UCL) and M. De Pasquale (MSSL-UCL) report on 
behalf of the Swift/UVOT team:

The Swift/UVOT began settled observations of the field of GRB 130305A 
30975s after the BAT trigger discovered in ground analysis (Cummings et 
al., GCN Circ. 14257).
No optical afterglow consistent with the XRT position (Malesani et al., 
GCN Circ. 14263) is detected in the initial UVOT exposures. Preliminary 
3-sigma upper limit using the UVOT photometric system (Breeveld et al. 
2011, AIP Conf. Proc. 1358, 373) for the initial exposures are:

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

u                30975        59030         3890         >21.4

The magnitudes in the table are not corrected for the Galactic 
extinction due to the reddening of E(B-V) = 0.05 in the direction of the 
burst (Schlegel et al. 1998).