Radio detection of GRO J1655-40
ATel #419; M. P. Rupen (NRAO/GSFC), V. Dhawan, A. J. Mioduszewski (NRAO)
on 21 Feb 2005; 19:44 UT
Credential Certification: Michael P. Rupen (mrupen@nrao.edu)
Subjects: Radio, Binary, Black Hole, Transient
We report the detection of renewed radio activity associated with the black
hole X-ray binary GRO J1655-40, currently undergoing an X-ray (ATEL #414;
ATEL #415) and optical/infrared (ATEL #417, ATEL #418) flare.
Very Large Array (VLA) observations taken on Feb. 20th (MJD 53421.6) under
poor weather conditions clearly detect a 1.4+/-0.2 mJy source at the position of
GRO J1655-40 at 4.86 GHz, and a corresponding 1.1+/-0.4 mJy source
(uncertainties dominated by phase errors) at 8.46 GHz. There is no obvious
extension with our 5.35 x 2.67 arcsec beam (oriented -5 degrees east of north)
at 4.86 GHz; the 8.46 GHz do not place any useful limit. Our last previous
observations were made on 4 January 2005 (MJD 53374.6) at 4.86 GHz, yielding
a non-detection with an rms noise of 0.13 mJy/beam. Further radio
observations are planned.
The National Radio Astronomy Observatory is a facility of the National
Science Foundation operated under cooperative agreement by Associated
Universities, Inc.
