Radio observations of H1743-322 = IGR J1746-3213 = XTE J17464-3213
M. P. Rupen, V. Dhawan, A. J. Mioduszewski (NRAO)
We report Very Large Array (VLA) observations of the black hole candidate binary H1743-322 = IGR J1746-3213 = XTE J17464-3213, currently undergoing an X-ray outburst (ATEL #301). Data taken on 11 July 2004 show no detections at 4.86 and 8.46 GHz, with nominal flux densities at the position of the source of 0.17 +/- 0.23 mJy/beam and 0.10 +/- 0.08 mJy/beam respectively. Observations on 27 June 2004 also showed no source, the nominal flux density being 0.07 +/- 0.07 mJy/beam at 8.46 GHz. Regular monitoring observations at one to two week intervals gave a possible (3sigma) detection of the core on 9 April 2004 (0.15 +/- 0.05 mJy/beam at 4.86 GHz). The last clearly believable detection was however towards the end of the X-ray hard state (ATEL #198), on 6 November 2003, when the flux density was 0.22 +/- 0.04 mJy at 4.86 GHz. Further radio observations are planned at few-day to weekly intervals.

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radio,x-ray,binary,black hole,star,transient,variables