General Relativistic Stream Crossing in Tidal Disruption Events

Understand

When a star is tidally disrupted by a supermassive black hole (BH), the gas debris is stretched into an elongated stream.

• The longitudinal motion of the stream follows geodesics in the Kerr spacetime and the evolution in the transverse dimensions is decoupled from the longitudinal motion.
• Using an approximate tidal equation, we calculate the evolution of the stream thickness along the geodesic, during which we treat the effect of nozzle shocks as a perfect bounce.
• Intersection occurs when the thickness exceeds the closest approach separation.