Dr. Indu Dihingia

Relativistic jets and disc-winds are typically observed in BH-XRBs and AGNs. However, many physical details of jet launching and the driving of disc winds from the underlying accretion disc are still not fully understood. We have performed axisymmetric GRMHD simulations of the accretion-ejection system using AMR. Essentially, our simulations were initiated with a thin accretion disc in equilibrium. I will present results from our extensive parametric study with different combinations of initial magnetic field strength and inclination parameter (m). With these simulations, I will examine the role of the magnetic field strength and structure in launching jets and driving disc-winds. I will also discuss the connection between jet, wind, and the accretion disc around the central black hole. Our study has found relativistic jets and disc-wind driven by the Blandford & Znajek and Blandford & Payne mechanism, respectively. We have also found that plasmoids are formed due to the reconnection events, and these plasmoids advect with disc-winds. Consequently, the enhanced magnetic tension force results in disc truncation and oscillation in the inner part of the accretion disc. The plasma-beta and m play crucial roles in the evolution of the accretion-ejection system, which I will discuss in detail. Further, I will also discuss possible applications of our models to understand spectral state transition phenomena in BH-XRBs.