## 4. Parameters used in the simulationTo calculate the effects of dynamical friction, introduced in the
previous section, on a disc-like structure as KB, we cannot use the
classical Chandrasekhar (1943) theory but we need equations specified
for distributions like KB. These equations were written in the
previous section (Eqs. 8 - 11). To calculate the effect of dynamical
friction on the orbital evolution of the largest bodies we suppose
that and
are constants and that
=.
We need also the mass density distribution in the disc. We assume a
heliocentric ( We remember also that the KB is a disc and then we use the mass distribution given by a Myiamoto-Nagai disc (Binney & Tremaine 1987; Wiegert & Tremaine 1997): which in the disc plane reproduces the quoted surface density and
Eq. (15) . Here © European Southern Observatory (ESO) 1999 Online publication: October 4, 1999 |