[vsnet-grb-info 18353] GRB 160815A: Swift/UVOT Detection

[GCN Circulars]

TITLE:   GCN CIRCULAR
NUMBER:  19801
SUBJECT: GRB 160815A: Swift/UVOT Detection
DATE:    16/08/16 21:53:24 GMT
FROM:    Mike Siegel at PSU/Swift MOC  <siegel at swift.psu.edu>

S.J. LaPorte (PSU) and C. B. Markwardt (NASA/GSFC)
report on behalf of the Swift/UVOT team:

The Swift/UVOT began settled observations of the field of GRB 160815A
90 s after the BAT trigger (Markwardt et al., GCN Circ. 19794). We detect a
fading source consistent with the XRT position (Beardmore et al. GCN Circ.
19796).

Preliminary detections 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           90             239       146     18.17+-0.14   
white          582            5549       402    >19.72   
v              632            5960       274    >17.99   
b              557            5344       254    >18.64   
u              301            6449       554    >18.85   
uvw1           681            6370       432    >18.67   
uvm2           656            6165       274    >18.64   
uvw2           607            5755       274    >18.70   


The magnitude is not corrected for the Galactic extinction
due to the reddening of E(B-V) = 0.12 in the direction of the burst
(Schlegel et al. 1998).