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Radio / X-ray correlation in the low/hard state of GX 339--4

S. Corbel·M. A. Nowak·R. P. Fender·A. K. Tzioumis·S. Markoff
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Abstract

We present the results of a long-term study of the black hole candidate GX 339-4 using simultaneous radio (from the Australia Telescope Compact Array) and X-ray (from the Rossi X-ray Timing Explorer and BeppoSAX) observations performed between 1997 and 2000. We find strong evidence for a correlation between these two emission regimes that extends over more than three decades in X-ray flux, down to the quiescence level of GX 339-4. This is the strongest evidence to date for such strong coupling between radio and X-ray emission. We discuss these results in light of a jet model that can explain the radio/X-ray correlation. This could indicate that a significant fraction of the X-ray flux that is observed in the low-hard state of black hole candidates may be due to optically thin synchrotron emission from the compact jet.

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S. Corbel, M. A. Nowak, R. P. Fender, A. K. Tzioumis, S. Markoff. 2003-01-22. Radio / X-ray correlation in the low/hard state of GX 339--4. https://doi.org/10.1051/0004-6361%3A20030090

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