GCN Circular 7758
Subject
GRB080520: Swift/UVOT observations
Event
Date
2008-05-21T13:12:58Z (17 years ago)
From
Samantha Oates at MSSL  <sro@mssl.ucl.ac.uk>
S.R. Oates (MSSL/UCL) and D. Grupe (PSU) report on behalf of
the Swift/UVOT team
The Swift/UVOT began settled observations of the field of GRB 080520, 105s 
after the BAT trigger (Grupe et al., GCN 7753). We detect the afterglow in 
the white, v filters at the position:
RA(J2000.0)  =  18:40:46.30
DEC(J2000.0) = -54:59:31.0
with an estimated uncertainty of 0.5 arcsec (radius, 90% confidence).
This position is consistent with the UVOT enhanced XRT position (Goad et 
al., GCN 7755).
UVOT magnitudes and 3 sigma upper limits are reported below for the single
and coadded images:
Filter    Tstart(s)  Tstop   Expo(s)   Magnitude/3sigUL
-----------------------------------------------------
white       105      204    98       19.59 +/- 0.12
white       858      958    98       20.58 +/- 0.28
v           211      610    400      20.26 +/- 0.38
v           964      1299   330      19.96 +/- 0.45
b           691      6273   216      > 20.92
u           666      6068   197	     > 20.60
w1          641      5862   236      > 20.33
m2          617      7079   418      > 20.38
w2          720      6684   216      > 20.25
-----------------------------------------------------
These magnitudes are not corrected for the Galactic extinction
corresponding to a reddening of E{B-V} = 0.08 mag (Schlegel et al.
1998). The photometry is on the UVOT flight system described in Poole
et al. (2008, MNRAS, 383, 627).