GCN Circular 8249
Subject
GRB080916A: Refined Swift/UVOT Observations
Event
Date
2008-09-16T19:58:10Z (17 years ago)
From
Samantha Oates at MSSL <sro@mssl.ucl.ac.uk>
S. R. Oates (UCL-MSSL) and H. Ziaeepour (UCL-MSSL) report on
behalf of the Swift/UVOT team:
The Swift/UVOT began settled observations of the field of
GRB 080916A, 78s after the BAT trigger (Ziaeepour et al., GCN 8237).
We detect the afterglow in all of the UVOT filters at the position:
RA(J2000.0) = 22:25:06.20
DEC(J2000.0) = -57:01:22.9
with an estimated uncertainty of 0.5 arcsec (radius, 90% confidence).
This position is consistent with the UVOT enhanced XRT position (Evans et
al., GCN 8241) and the REM position (Fugazza et al., GCN 8238).
UVOT magnitudes are reported below for the finding charts (fc) and images:
Filter Tstart(s) Tstop Expo(s) Magnitude/3sigUL
-----------------------------------------------------
white (fc) 78 178 98 18.33 +/- 0.06
white 872 972 98 18.47 +/- 0.06
v (fc) 182 582 393 17.55 +/- 0.06
v 978 1378 393 18.39 +/- 0.11
b 1458 1477 19 18.90 +/- 0.35
u 538 658 19 17.53 +/- 0.19
w1 613 633 19 18.25 +/- 0.39
m2 741 1565 39 18.42 +/- 0.40
w2 692 864 39 18.75 +/- 0.37
-----------------------------------------------------
These magnitudes are not corrected for the Galactic extinction
corresponding to a reddening of E{B-V} = 0.02 mag (Schlegel et al.
1998). The photometry is on the UVOT flight system described in Poole
et al. (2008,MNRAS,383,627).