Line-force driven wind from a thin disk in tidal disruption event

TL;DR

This study uses hydrodynamic simulations to show that line-force driven winds from sub-Eddington accretion disks in tidal disruption events can reach high velocities and carry significant energy, influencing observable emissions.

Contribution

It provides the first detailed analysis of line-force driven winds from sub-Eddington disks in TDEs using 2D hydrodynamic simulations.

Findings

Strong winds can be driven when luminosity exceeds 20% of Eddington.

Wind velocities can reach up to 0.3 times the speed of light.

Kinematic power of winds is 1-6% of Eddington luminosity.

Abstract

Winds from the accretion disk in tidal disruption events (TDEs) play a key role in determining the radiation of TDEs. The winds from the super-Eddington accretion phase in TDEs have recently been studied. However, properties of the winds from the sub-Eddington accretion disk in TDEs are not clear. We aim to investigate properties of winds from the circularized sub-Eddington accretion disk in TDEs. We study the line force driven accretion disk wind. We perform two-dimensional hydrodynamic simulations using the PLUTO code to study the line force driven wind from the circularized accretion disk around a $10^6$ solar mass black hole in TDEs. We find that although the disk has a very small size in TDEs, strong wind can be driven by line force when the disk have luminosity higher than $20\%$ of the Eddington luminosity. The maximum velocity of wind can be as high as $0.3$ times the speed of light. The kinematic power of wind is in the range of $1\%-6\%$ times the Eddington luminosity. Strong wind can be driven by line force from the thin disk around a $10^6$ solar mass black hole in TDEs. We briefly discuss the possible radio emission from the shock when the wind collides with the surrounding medium.