A phase lag between disc and corona in GRMHD simulations of precessing tilted accretion discs

In the course of its evolution, a black hole (BH) accretes gas from wide range directions. Given random accretion event, typical angular momentum an disc would be tilted by ∼60∘ relative to BH spin. Misalignment causes precess at rate that increases with spin and depends on morphology. We present general-relativistic magnetohydrodynamic (GRMHD) simulations spanning full precession period highly (60∘), moderately thin (h/r=0.1) discs around rapidly spinning (a≃0.9) BH. While jets in phase, we find wind/corona, sandwiched between two, lags behind ≳10°. For spectral models accretion, implication is hard non-thermal (corona) emission softer (disc) emission, thus potentially explaining some properties energy seen Type-C low frequency quasi-periodic oscillations X-ray binaries. strong are unaffected this disc-corona lag, weak can stall when encountering lagging corona distances r∼100 radii. This interaction may quench large-scale jet formation.