GCN Circular 5397

S. B. Pandey, M. De Pasquale, M. J. Page and 
H.Z. Ziaeepour (UCL-MSSL) report on behalf of the 
Swift/UVOT team:

The Swift UVOT began taking settled exposures
on the field of the long duration GRB 060804
(BAT Trigger #222546), 128s after the BAT trigger
(Ziaeepour et al., GCN Circ. 5394
Not found
 
 
). The optical
afterglow candidate (RA(J2000) = 07h 28m 49.36s
Dec(J2000) = -27d 12' 56.7") reported by Ziaeepour 
et al. 2006 (GCN Circ. 5394
Not found
 
 
) is clearly detected in 
early frames. The fading behaviour of the candidate 
before the later frames confirms that it is the 
afterglow of GRB 060804. Detections in the initial 
V and White images, and 3-sigma upper limits in the 
later, coadded images are listed below.

Filter  T_range(s)    Exposure (s)    Magnitude

White   126-225         98            17.9+-0.1
V       231-631         393           17.7+-0.1


Filter  T_range(s)    Exposure (s)    3-sigma UL

White   5211-12280      253           > 20.1
V       5621-5820       197           > 19.4
B       709-12219       944           > 20.5
U       685-18065       896           > 19.9
UVW1    661-15696       408           > 19.8
UVM2    637-6025        216           > 19.5
UVW2    5417-21845      747           > 19.7

T_range is calculated from the time of the trigger.
We caution that photometry of this afterglow
is complicated by the presence of a nearby source.

These measurements have not been corrected for the
estimated Galactic reddening of E_(B-V) = 0.657 mag
(Schlegel et al. 1998). We caution that the 
extinction estimate for this burst, which has
|Galactic latitude| < 5 deg, is unreliable.