Speaker
Description
Polarity inversion events of black hole jets have been proposed to explain state transitions of X-ray binaries or certain changing-look AGNs. Such events can be triggered by magnetic fields of opposite polarity being accreted onto the black hole, causing the jet to shut down and reform with reversed polarity. To investigate this, we conducted axisymmetric general relativistic magnetohydrodynamic (GRMHD) simulations of an accretion torus initially threaded by two magnetic field components of opposite polarity, with the polarity inversion occurring at distinct radial locations. In the early stages, the black hole produces a relativistic Blandford–Znajek jet powered by accretion, which is subsequently quenched and disrupted, followed by the re-emergence of a jet with reversed magnetic polarity as accretion continues.