Disk-Jet coupling in Galactic Black Hole X-ray Binaries: Disk Dynamics and Jet Velocity

We carry out broad-band spectro-temporal analysis of RXTE and HXMT data of twelve galactic Black Hole X-ray Binaries (BH-XRBs) to investigate the disk-jet connection. The temporal analysis of these sources indicate the presence of type-C QPOs during LHS and HIMS, when Comptonised emission is dominant (Fnth ≥ 0.4). In contrast, type-A and type-B QPOs are observed near radio flares during SIMS, characterised by weak Comptonised emission (Fnth ≤ 0.3). Type-A QPOs exhibit a negative lag (1−10 ms) for all sources and act as a precursor to the ejection events. On the other hand, type-B QPOs show a positive lag (1 − 20 ms), irrespective of the inclination angle, despite having similar Comptonised emission as that of type-A QPOs. Based on this, we infer an alteration in the geometry of corona during the appearance of type-B QPOs which eventually gets ejected as jet. In addition, the jet velocity calculated during the radio flares indicates the relativistic nature (β ≥ 0.55) of jets during SIMS. Furthermore, the positive correlation observed between the radio and X- ray luminosities indicates that the jets are powered by accretion process. Finally, we discuss the possible disk dynamics in the context of accretion flow.