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High- and low-frequency quasi-periodic oscillations in the X-ray light curves of the black hole transient H1743-322

Jeroen Homan·Jon M. Miller·Rudy Wijnands·Michiel van der Klis·Tomaso Belloni·Danny Steeghs·Walter H. G. Lewin
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Abstract

We present a variability study of the black hole candidate and X-ray transient H1743-322 during its 2003/2004 outburst. We analyzed five Rossi X-ray Timing Explorer observations that were performed as part of a multi-wavelength campaign, as well as six observations from the early rise of the outburst. The source was observed in several black hole states and showed various types of X-ray variability, including high frequency quasi-periodic oscillations (QPOs) at 240 Hz and 160 Hz (i.e. with a 3:2 frequency ratio), several types of low frequency QPOs, and strong variations on a time scale of a few hundred seconds. The discovery of high frequency QPOs in H1743-322 supports predictions that these QPOs should be more easily observed in high inclination systems. In one of our observations we observed a transition in count rate and color, during which we were able to follow the smooth evolution of the low-frequency QPOs from type-B to type-A. We classify the X-ray observations and QPOs, and briefly discuss the QPOs in terms of recently proposed models.

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Jeroen Homan, Jon M. Miller, Rudy Wijnands, Michiel van der Klis, Tomaso Belloni, Danny Steeghs, Walter H. G. Lewin. 2004-06-14. High- and low-frequency quasi-periodic oscillations in the X-ray light curves of the black hole transient H1743-322. https://doi.org/10.1086/424994

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