GCN Circular 3733
Subject
GRB050801: Swift/UVOT Optical and UV detections
Date
2005-08-02T07:57:28Z (19 years ago)
From
Alexander Blustin at MSSL-UCL <ajb@mssl.ucl.ac.uk>
A. J. Blustin (UCL-MSSL), D. Band (GSFC), S. Hunsberger (PSU),
C. Gronwall (PSU), M. Carter (UCL-MSSL), P. Smith (UCL-MSSL)
on behalf of the Swift/UVOT team report:
The Swift/UVOT began observing the afterglow of GRB050801 at
2005-08-01T18:32:00, 238 s after the BAT trigger (Band et al.,
GCN 3725). The afterglow was detected in all six optical and
UV filters at a position (J2000, corrected to the DSS
coordinates) of:
RA 13:36:35 (+/- 1 arcsec)
DEC -21:55:41 (+/- 1 arcsec)
We give two lightcurve points for each filter in the table
below so that decay slopes may be determined.
Filter T_mid Exp Magnitude
V 244 9.78 15.9 +/- 0.2
V 919 9.77 17.9 +/- 0.8
B 215 9.78 16.0 +/- 0.1
B 890 9.78 18.0 +/- 0.4
U 201 9.78 15.20 +/- 0.09
U 961 9.76 17.2 +/- 0.3
UVW1 187 9.78 15.5 +/- 0.1
UVW1 11316 899.77 20.1 +/- 0.3
UVM2 173 9.78 16.0 +/- 0.2
UVM2 6590 337.06 20.6 +/- 0.9
UVW2 230 9.78 17.4 +/- 0.4
UVW2 4524 670.56 21.0 +/- 0.4
Where Tmid is the midpoint of the exposure post-trigger in seconds.
The magnitudes are based on preliminary zero points, measured in
orbit, and will require refinement with further calibration. All
magnitudes are uncorrected for Galactic reddening.