[vsnet-grb-info 3533] GRB 060729: Swift/UVOT Observations

[GCN Circulars]

TITLE:   GCN GRB OBSERVATION REPORT
NUMBER:  5367
SUBJECT: GRB 060729: Swift/UVOT Observations
DATE:    06/07/29 23:33:34 GMT
FROM:    Stefan Immler at NASA/GSFC  <immler at milkyway.gsfc.nasa.gov>

S. Immler (NASA/USRA/GSFC) reports on behalf of the Swift/UVOT team:

The Swift/UVOT began observing the field of GRB 060729 at
19:14:45 UT on 2006-07-29, 135 s after the BAT trigger (Grupe et al.,
GCN 5365). An optical counterpart was detected in the White
(160-650 nm) and V filters at a position of RA, Dec = 06:21:31.85,
-62:22:12.7 (J2000), located within the XRT error circle.

A White filter image taken 12 min later showed that the source
brightened by about 1 magnitude, while the source stayed constant
in images obtained in the V filter within the same period.
The photometry results are given for the UVOT filters below:

Filter   T_start(s)  Exposure(s)    Mag

White     135         100        17.75
White     860         100        16.65
V     241         396        17.30
V     966         400        17.35

Statistical and systematic errors are 0.1 mag each.
The values quoted above are not corrected for the expected
Galactic extinction of E_{B-V}=0.054 (Schlegel et al. 1998).
More UVOT data are expected after the next Malindi contact
(2006-07-30 01:27 UT).