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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 $ u$ $sim$ 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.
We observed the Galactic black hole candidate H1743-322 with Suzaku for approximately 32 ksec, while the source was in a low/hard state during its 2008 outburst. We collected and analyzed the data with the HXD/PIN, HXD/GSO and XIS cameras spanning th
We report the discovery of quasi-periodic oscillations (QPO) at ~11 mHz in two RXTE observations and one Chandra observation of the black hole candidate H1743-322. The QPO is observed only at the beginning of the 2010 and 2011 outbursts at similar ha
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 meas
It has long been proposed that low frequency QPOs in stellar mass black holes or their equivalents in super massive black holes are results of resonances between infall and cooling time scales. We explicitly compute these two time scales in a generic
We present the results of the analysis of a large database of X-ray observations of 22 galactic black-hole transients with the Rossi X-Ray timing explorer throughout its operative life for a total exposure time of ~12 Ms. We excluded persistent syste