J. C. A. Miller-Jones, G. R. Sivakoff, D. Altamirano, M. Coriat, S. Corbel, V. Dhawan, H. A. Krimm, R. A. Remillard, M. P. Rupen, D. M. Russell, R. P. Fender, S. Heinz, E. G. Körding, D. Maitra, S. Markoff, S. Migliari, C. L. Sarazin, V. Tudose
We present an intensive radio and X-ray monitoring campaign on the 2009
outburst of the Galactic black hole candidate X-ray binary H1743-322. With the
high angular resolution of the Very Long Baseline Array, we resolve the jet
ejection event and measure the proper motions of the jet ejecta relative to the
position of the compact core jets detected at the beginning of the outburst.
This allows us to accurately couple the moment when the jet ejection event
occurred with X-ray spectral and timing signatures. We find that X-ray timing
signatures are the best diagnostic of the jet ejection event in this outburst,
which occurred as the X-ray variability began to decrease and the Type C
quasi-periodic oscillations disappeared from the X-ray power density spectrum.
However, this sequence of events does not appear to be replicated in all black
hole X-ray binary outbursts, even within an individual source. In our
observations of H1743-322, the ejection was contemporaneous with a quenching of
the radio emission, prior to the start of the major radio flare. This
contradicts previous assumptions that the onset of the radio flare marks the
moment of ejection. The jet speed appears to vary between outbursts, with a
possible positive correlation with outburst luminosity. The compact core radio
jet reactivated on transition to the hard intermediate state at the end of the
outburst, and not when the source reached the low hard spectral state.
Comparison with the known near-infrared behaviour of the compact jets suggests
a gradual evolution of the compact jet power over a few days near the beginning
and end of an outburst.
View original:
http://arxiv.org/abs/1201.1678
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