[vsnet-grb-info 9626] Swift/UVOT observations of GRB100814A

[GCN Circulars]

TITLE:   GCN CIRCULAR
NUMBER:  11095
SUBJECT: Swift/UVOT observations of GRB100814A
DATE:    10/08/14 15:26:23 GMT
FROM:    Patricia Schady at MPE/Swift  <msslba at googlemail.com>

M. De Pasquale (MSSL-UCL) and C.J. Saxton (MSSL-UCL)
report on the behalf of the Swift UVOT team:

 The Swift/UVOT began settled observations of the field of
GRB 100814A 153 s after the BAT trigger  (Beardmore et
al. 2010, GCN Circ. 11087) with a finding chart in the u
filter. We detect the optical afterglow in all filters except
uvw2. The refined UVOT position is

 RA  (J2000) = 01h 29m 53.61s = 22.47338
 Dec (J2000) = -17d 59m 43.6s = -17.99545


with an estimated uncertainty of 0.6 arcsec (radius, 90% confidence,
statistical + systematic). This is about 1.5 arcsec north of the
UVOT-enhanced XRT position (Beardmore et al. 2010, GCN Circ.
11092).

 Preliminary magnitudes, and 3-sigma upper limits for detecting a
source in the finding charts and in co-added images are

Filter      T_start   T_stop    Exp(s)      Mag   Err
---------------------------------------------------------------------
   u (fc)      153      403        246      16.80  0.06
   v            458      627         39       17.91  0.32
   b            408      721         53       21.22  0.20
   u            153      701       285       16.84  0.06
 uvw1        507      676         39       17.33  0.20
 uvm2       483       651         39       17.86  0.31
 uvw2        434      602          39    >18.52  3-sigma UL
 white      3858     4211        344      18.63  0.07
-----------------------------------------------------------

 The quoted magnitudes and upper limits have not been corrected
for the expected Galactic extinction along the line of sight
corresponding to a reddening of E_{B-V} = 0.02 mag (Schlegel, et al.,
1998, ApJS, 500, 525). Â All photometry is on the UVOT photometry
system described in Poole et al. (2008, MNRAS, 383, 627).