GCN Circular 7905
Subject
GRB 080625: Swift/UVOT Detection of an Optical Afterglow
Date
2008-06-26T02:09:08Z (16 years ago)
From
Stefan Immler at NASA/GSFC <stefan.m.immler@nasa.gov>
S. Immler (NASA/CRESST/GSFC) reports on behalf of the Swift/UVOT team:
The Swift Ultra-Violet/Optical Telescope (UVOT) started observing
GRB 080625 (Pacciani et al., GCN Circ. 7903) ~5.0 hours after the
AGILE trigger.
A candidate afterglow is found in UVOT White, v, and b filter
images which cover the entire AGILE error circle. The preliminary
Swift/UVOT position of the optical afterglow candidate is:
RA(J2000) = 19:53:37.06 = 298.4044
DEC(J2000) = +56:16:40.5 = 56.2779
with a 1-sigma error radius of about 0.5 arcsec.
The following table gives the measured magnitudes:
Filter T_start [s] T_stop [s] Exp [s] Magnitude
White 18769 19567 799 20.3 +/- 0.1
White 24551 25179 1427 20.6 +/- 0.1
V 19575 20350 776 19.6 +/- 0.1
B 17964 18762 799 20.1 +/- 0.1
B 23746 24544 799 20.7 +/- 0.2
U 17880 23741 240 >20.4 (3-sigma UL)
The values quoted above are in the UVOT photometric system
(Poole et al. 2008, MNRAS, 383, 627). No correction has been
made for the expected extinction corresponding to E(B-V) of
0.44 mag in the direction of the burst (Schlegel et al. 1998).