TITLE:   GCN GRB OBSERVATION REPORT
NUMBER:  5219
SUBJECT: GRB060604: Swift/UVOT detections
DATE:    06/06/05 14:25:51 GMT
FROM:    Alexander Blustin at MSSL-UCL  <ajb@mssl.ucl.ac.uk>

A. J. Blustin (UCL-MSSL) and M. J. Page (UCL-MSSL) report on behalf
of the Swift/UVOT team:

The Swift/UVOT began observing the field of GRB060604 at 18:20:39
on 2006-06-04, 100 s after the BAT trigger (Page et al., GCN 5212).
The afterglow candidate at the position reported by Page et al.
(GCN 5212) was detected at greater than 2 sigma significance in the
V, B, U, UVW1 and White filters. Magnitudes and 3-sigma upper limits
from co-added images in the colour filters, and from two single
images in the White filter, are given below. The weak detection in
the UVW1 band is consistent with the tentative redshift of 2.68
reported by Castro-Tirado et al. (GCN 5218).

Filter  T_range(s)  Exposure(s)  Mag/3sig_UL     Significance (sigma)
V       100-10165   1127         21.2 +/- 0.6    2.4
B       4086-23420  1956         21.2 +/- 0.2    5.8
U       3881-29206  2705         21.1 +/- 0.2    4.4
UVW1    3677-28601  2900         22.1 +/- 0.4    2.8
UVM2    3472-27694  2139         21.1 (3sig_UL)
UVW2    4496-6061   321          19.8 (3sig_UL)

White   117-217     98           18.3 +/- 0.1    13.4
White   4290-4490   190          20.5 +/- 0.3    3.9

These magnitudes are uncorrected for Galactic extinction
(E(B-V) = 0.043).