[vsnet-grb-info 15770] GRB 141109B: Swift/UVOT Upper Limits

[GCN Circulars]

TITLE:   GCN CIRCULAR
NUMBER:  17058
SUBJECT: GRB 141109B: Swift/UVOT Upper Limits
DATE:    14/11/10 22:56:56 GMT
FROM:    Frank Marshall at GSFC  <femarsha at khamseen.gsfc.nasa.gov>

F. E. Marshall (NASA/GSFC) and A. Melandri (INAF-OAB)
report on behalf of the Swift/UVOT team:

The Swift/UVOT began settled observations of the field of GRB 141109B
188 s after the BAT trigger (Melandri et al., GCN Circ. 17038).
No optical afterglow consistent with the UVOT-enhanced XRT position
(Beardmore et al., GCN Circ. 17045)
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           188          338          147         >20.1
u_FC               347          596          246         >20.4
white              188         6699          588         >21.3
v                  677         7110          313         >20.4
b                  602         6494          294         >21.0
u                  347        13125         1061         >20.9
w1                 727        12566         1207         >21.0
m2                 701         7315          255         >20.8
w2                 828         6905          255         >21.0

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).