# Tilted Disks around Black Holes: A Numerical Parameter Survey for Spin and Inclination Angle

## TL;DR

This study explores how tilted accretion disks around spinning black holes behave, revealing complex precession, shock formation, and impacts on flow efficiency through extensive numerical simulations.

## Contribution

It provides a comprehensive numerical survey of tilted disk properties across various black hole spins and tilt angles, highlighting new flow dynamics and shock effects.

## Key findings

- Tilted disks precess rigidly around black hole spin axes.
- Standing shocks form at high inclinations, affecting angular momentum transport.
- High spins lead to more effective material redirection and reduced radiative efficiency.

## Abstract

We conduct a systematic study of the properties of tilted accretion flows around spinning black holes, covering a range of tilt angles and black hole spins, using the general-relativistic magnetohydrodynamics code Athena++. The same initial magnetized torus is evolved around black holes with spins ranging from 0 to 0.9, with inclinations ranging from 0 degrees to 24 degrees. The tilted disks quickly reach a warped and twisted shape that rigidly precesses about the black hole spin axis with deformations in shape large enough to hinder the application of linear bending wave theory. Magnetized polar outflows form, oriented along the disk rotation axes. At sufficiently high inclinations a pair of standing shocks develops in the disks. These shocks dramatically affect the flow at small radii, driving angular momentum transport. At high spins they redirect material more effectively than they heat it, reducing the dissipation rate relative to the mass accretion rate and lowering the radiative efficiency of the flow.