Title:
Bound debris in stellar tidal disruption events

Abstract:
Highly energetic stellar tidal disruptions (TDEs) provide a way 
to study supermassive black hole characteristics and their environment. 
After a tidal disruption event matter can be bound or unbound, 
depending on its total energy. A key issue in understanding TDEs, 
disk formation and their light curves, is the amount of matter, 
which either falls in the black hole, forms a disk or escapes in the interstellar space. 
We investigate, how a ratio between mass of bound and total mass of the debris 
evolves with time, taking stars on orbits with different eccentricities and penetration factors. 
Our analysis is based on results derived from hydrodynamical simulations 
with the PHANTOM code in generalized Newtonian potential. 
We also calculate total energy, angular momentum and energy spread 
in order to ascertain their connection to the amount of bound debris. 
We confirm, that the extent of bound matter is related to the energy/angular momentum 
before disruption and to the increase in energy/angular momentum induced by 
tidal forces during the first encounter. In the case of hyperbolic 
and parabolic orbits we conclude, that the amount of bound debris is decreasing 
with the penetration factor.