GCN Circular 1025
Subject
GRB010220, field photometry
Date
2001-03-28T19:12:57Z (24 years ago)
From
Arne A. Henden at USNO/USRA <aah@nofs.navy.mil>
A. Henden (USRA/USNO) reports on behalf of the USNO GRB team:
We have acquired shallow BVRcIc all-sky photometry for
an 11x11 arcmin field that covers the BeppoSAX
error circle for GRB010220 (GCN 956) with the USNOFS 1.0-m telescope
on one marginally photometric night. Stars brighter than
V=13 are saturated and should be used with care.
We have placed the photometric data on our anonymous ftp site:
ftp://ftp.nofs.navy.mil/pub/outgoing/aah/grb/grb010220.dat
The current photometry has a potential external zero-point
error of about three percent. The astrometry in this file
is based on linear plate solutions with respect to USNO-A2.0.
The internal errors are less than 100mas. Crowding will
yield some unphysical stars due to astrometric and photometric
blends.
Further calibration of this field will not be performed this
season as the field is disappearing into twilight.