Talk detail

Participant	Arca sedda, manuel
Institution	University of Rome "Sapienza" - Piazzale Aldo Moro, 5 - rome - Italy - Italy

Session	EG4	Accepted		Order	Time
Talk	Oral abstract	Title	Dynamical friction in cuspy galaxies
Co-authors
Abstract	The classic Chandrasekhar treatment of dynamical friction fails when dealing with the motion of objects in the inner region of a galaxy which shows a cuspidal distribution of stars around its center. Here we present results concerning the orbital decay of massive objects moving in a cuspy galaxy as obtained by self-consistent direct N-body simulations as well as by a new semi-analytical treatment of dynamical friction valid in the central region of a spherical galaxy modeled with a double divergent distribution function and in presence of a local massive black hole. A comparison of these results indicate that the proposed semi-analytical approximation is not just the only acceptable in central, cuspy, regions but it also gives quantitatively satisfying approximations to the `true' (N-body) evaluations, providing reliable