Radio observations of XTE J1739-302/IGR J17391-3021
ATel #184; M. P. Rupen, A. J. Mioduszewski, V. Dhawan (NRAO)
on 29 Aug 2003; 23:26 UT
Credential Certification: Michael P. Rupen (email@example.com)
Subjects: Radio, X-ray, Gamma Ray, Binary, Transient
Referred to by ATel #: 338
Very Large Array (VLA) observations of the transient X-ray source
IGR J17391-3021 (possibly a recurrence of XTE J1739-302; ATEL #181)
on August 28 UT show one radio source at 4.86 GHz within the INTEGRAL
three arcminute error circle (ATEL #181), at
- 17 39 01.52 -30 19 34.9 (J2000)
where the position is accurate to ~0.2 arcseconds.
The flux density was 0.9+/-0.2 mJy, after accounting for the primary beam
(antenna) response. The detection was highly significant (9 sigma), and
the error bar reflects both random and systematic errors. This source is ~2
arcminutes from the nominal INTEGRAL position (ATEL #181
). Unfortunately the
image from the NRAO VLA Sky Survey (NVSS; Condon et al. 1998, AJ 115, 1693),
based on data taken at 1.4 GHz in 1995, is too confused to provide a useful
constraint on variability. Further VLA observations are planned.
There are no plausible counterparts to XTE J1739-302 in this radio
image, as all detected sources are more than two arcminutes from the Chandra
position (ATEL #182), which presumably is accurate to better than a few
arcseconds. The minimum and maximum observed radio surface brightnesses
within two arcseconds of that position are (-0.20,0.19) mJy/beam, after
correcting for primary beam attenuation.
- Observational details:
- The synthesized beam size was 1.2 x 0.4 arcsecond, with the major
axis oriented at a position angle of 20 degrees. The rms noise level
before primary beam correction was 0.08 mJy/beam, and the field was
centered on the reported INTEGRAL position (ATEL #181).
These observations were taken in spectral line mode to avoid
bandwidth smearing (chromatic aberration) in the current, most extended
VLA configuration (A configuration).
The National Radio Astronomy Observatory is a facility of the National
Science Foundation operated under cooperative agreement by Associated