[vsnet-grb-info 11290] GRB 111215B: Swift/UVOT Upper Limits

[GCN Circulars]

TITLE:   GCN CIRCULAR
NUMBER:  12702
SUBJECT: GRB 111215B: Swift/UVOT Upper Limits
DATE:    11/12/17 16:33:03 GMT
FROM:    Samantha Oates at MSSL  <sro at mssl.ucl.ac.uk>

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

The Swift/UVOT began settled observations of the field of the IPN-detected 
burst: GRB 111215B, 31.5 hrs after the IPN trigger (Hurley et al. et al. GCN Circ. 12698)
No optical afterglow consistent with the XRT position (Littlejohns et al. et al. GCN Circ. 12700)
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 initial exposures are:

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

u           113,256    130,435        4889         >21.4

The magnitudes in the table are not corrected for the Galactic extinction
due to the reddening of E(B-V) = 0.02 in the direction of the burst
(Schlegel et al. 1998).