[vsnet-grb-info 6229] Swift/UVOT Observations of GRB080607

[GCN Circulars]

TITLE:   GCN CIRCULAR
NUMBER:  7858
SUBJECT: Swift/UVOT Observations of GRB080607
DATE:    08/06/07 21:15:59 GMT
FROM:    Patricia Schady at MSSL/Swift  <ps at mssl.ucl.ac.uk>

P. Schady (MSSL/UCL) and V. Mangano (INAF-IASFPA) report on behalf of the
Swift UVOT team

The Swift UltraViolet/Optical Telescope (UVOT) began taking settled 
observations of GRB 080607 92 seconds after the initial Swift BAT trigger 
(Mangano et al., GCN Circ. 7847). A faint afterglow is detected in the first 
white and v-band finding chart exposures only at the refined uvot position of 
RA=194.94665, Dec=+15.91965 deg.(= 12:59:47.20 +15:55:10.74), with an accuracy 
of 0.5". This is consistent with the GRB being at a redshift of z=3.036, as 
reported in GCN Circ. 7849 (Prochaska et al.)

The first white and v-band finding chart magnitudes with 1-sigma errors are 
given below, as well as the 3-sigma upper limits for co-added images from later 
observations.

Filter Tmid(s) Exp(s)  Magnitude/3-sig UL
---------------------------------------------
wh     190.9     98.2    19.79 +/- 0.13
wh     4806.9    510.6   > 22.07
v      594.6     393.5   19.44 +/- 0.19
v      4048.5    300.2   > 20.11
b      5527.9    412.5   > 21.28
u      4934.2    432.2   > 20.93
uvw1   4934.2    432.1   > 20.80
uvm2   4745.1    432.1   > 20.57
uvw2   5745.6    358.5   > 20.83
---------------------------------------------

where Tmid is the weighted mid time of the observation. The values quoted above 
are on the UVOT Photometric System (Poole et al, 2008, MNRAS 383,627). They are 
not corrected for the expected galactic reddening of E(B-V) = 0.02 in the 
direction of the burst (Schlegel et al. 1998).