GCN Circular 6909

A. Henden (AAVSO) reports:

While the field of GRB071010B has been observed by SDSS, we have also
obtained a two-night BVRcIc field calibration using the 35cm robotic
telescope at Sonoita Research Observatory.  The calibration file
has a limiting magnitude around V=18, with good standards brighter
than V=16 or so.  The file is available at
ftp://ftp.aavso.org/public/calib/grb/grb071010b.dat

This calibration is based on numerous Landolt standards, and has
an external zeropoint error of about 0.02mag. We do not expect
at this time to extend this calibration to fainter magnitudes.

The AAVSO thanks the Curry Foundation for their continued support of the
AAVSO International High Energy Network.