[vsnet-grb-info 5173] GRB 071010B possible optical transient

[GCN Circulars]

TITLE:   GCN CIRCULAR
NUMBER:  6873
SUBJECT: GRB 071010B possible optical transient
DATE:    07/10/10 22:53:58 GMT
FROM:    AAVSO GRB Network at AAVSO  <aavsogrb at gmail.com>

A. Oksanen (Nyrola Observatory, Jyvaskyla, Finland) reports to the AAVSO
International High Energy Network the following optical observations of
GRB071010B (GCN #6871, Markwardt et al.):

Arto Oksanen reports the detection of an optical transient located at
RA 10:02:9.26, Dec +45:43:50.3 (J2000) at an initial unfiltered magnitude of

17.538 calibrated relative to USNOB R-band magnitudes.  Midpoint of the
exposures is 2007 Oct 10, 21:11:05 UTC, approximately 25 minutes after the
trigger.

There are no comparably bright stars within 0.5 arcminutes, and no minor
planets in the area.

Subsequent unfiltered images place the star fainter than 18th magnitude
(unfiltered) indicating the object has faded since observations began.
Analysis of additional unfiltered, Rc, Ic, and V images will be forthcoming.


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