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arXiv · 2103.02422

Spectro-temporal studies of rapid transition of the quasi periodic oscillations in the black hole source H1743-322

K. Sriram·S. Harikrishna·C. S. Choi
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Abstract

An appearance or disappearance of QPOs associated with the variation of X-ray flux can be used to decipher the accretion ejection mechanism of black hole X-ray sources. We searched and studied such rapid transitions in H1743-322 using RXTE archival data and found eight such events, where QPO vanishes suddenly along with the variation of X-ray flux. The appearance/disappearance of QPOs were associated to the four events exhibiting type-B QPOs at $\sim$ 4.5 Hz, one with type-A QPO at $\nu$ $\sim$ 3.5 Hz, and the remaining three were connected to type-C QPOs at $\sim$ 9.5 Hz. Spectral studies of the data unveiled that an inner disk radius remained at the same location around 2-9 r$_g$ , depending on the used model but power-law indices were varying, indicating that either corona or jet is responsible for the events. The probable ejection radii of corona were estimated to be around 4.2-15.4 r$_g$ based on the plasma ejection model. Our X-ray and quasi-simultaneous radio correlation studies suggest that the type-B QPOs are probably related to the precession of a weak jet though a small and weak corona is present at its base and the type-C QPOs are associated to the base of a relatively strong jet which is acting like a corona.

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K. Sriram, S. Harikrishna, C. S. Choi. 2021-03-03. Spectro-temporal studies of rapid transition of the quasi periodic oscillations in the black hole source H1743-322. https://doi.org/10.3847/1538-4357%2Fabe9ae

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