[vsnet-grb-info 14903] GRB 140430A: Swift/UVOT Observations

[GCN Circulars]

TITLE:   GCN CIRCULAR
NUMBER:  16198
SUBJECT: GRB 140430A: Swift/UVOT Observations
DATE:    14/05/01 11:42:29 GMT
FROM:    Alice Breeveld at MSSL-UCL  <a.breeveld at ucl.ac.uk>

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

The Swift/UVOT began settled observations of the field of GRB 140430A 
183 s after the BAT trigger (Siegel et al., GCN Circ. 16190). A fading 
source consistent with the refined XRT position (Evans et al. GCN Circ. 
16195) is confirmed in the initial UVOT exposures. The detection in the 
uvw1 filter, but not in uvm2 and uvw2 is consistent with the redshift of 
1.6 given by Kruehler et al., (GCN Circ. 16194).

Preliminary detections and 3-sigma upper limits using the UVOT 
photometric system (Breeveld et al. 2011, AIP Conf. Proc. 1358, 373) for 
the early exposures are:

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

white_FC           183          333          147         18.17 ± 0.09
white             4020         4220          197         19.61 ± 0.17
v                  417         4630          216        >18.6
b                 3815         4015          197         19.77 ± 0.34
u                10431        10933          490         19.46 ± 0.19
uvw1              6178        10424          966         20.40 ± 0.31
uvm2               442         4835          216        >19.9
uvw2               393         4425          216        >19.4

The magnitudes in the table are not corrected for the Galactic 
extinction due to the reddening of E(B-V) = 0.14 in the direction of the 
burst (Schlegel et al. 1998).