GCN Circular 6006
Subject
GRB070107 Swift/UVOT Observations of a Fading Optical Afterglow
Date
2007-01-10T17:04:52Z (17 years ago)
From
Padi Boyd at GSFC <padi@milkyway.gsfc.nasa.gov>
GRB 070107: UVOT Observations of a Fading Optical Afterglow
P. T. Boyd and F. E. Marshall (NASA/GSFC) report on behalf of the Swift team:
UVOT observed the field of GRB 070107 (Stamatikos et al. GCN Circ. 5999).
The complete data set through T=117,471s now available clearly shows a
fading source at the position reported by Boyd et al. (GCN Circ 6002).
This afterglow candidate is visible at early times in the White and
V filters, and probably also in the U filter.
The table below gives the measured magnitudes after correcting for
flux in the source aperture due to the bright (V=15.9 mag) nearby
star. Reported significance levels were calculated based on rates
in the source region, while magnitude errors include the contribution
from aperture correction.
Filter TSTART Exposure Mag Error Significance
White 181 98 19.5 0.3 5.6
White 5355 197 20.5 0.3 3.5
V 286 393 19.2 0.3 3.9
V 971 393 19.8 0.4 2.0
U 29220 590 20.6 0.4 2.8
B 5151 197 20.7 (3sigma UL)
W1 6174 197 20.0 (3sigma UL)
M2 16718 886 20.5 (3sigma UL)
W2 22501 886 20.8 (3sigma UL)
These magnitudes have not been corrected for the large and unreliable
Galactic extinction at this position.