The main topic of this paper is the investigation of the modes of interaction
of globular clusters (GCs) moving in the inner part of a galaxy. This is
tackled by means of high-resolution N-body simulations, whose first results are
presented in this article. Our simulations dealt with primordial very massive
(order of 10^7 solar masses) GCs that were able to decay, because of dynamical
friction, into the inner regions of triaxial galaxies on a time much shorter
than their internal relaxation time. To check the disruptive role of both tidal
forces and GC-GC collisions, we maximised the tidal interaction considering GCs
on quasi-radial orbits.
The available CPU resources allowed us to follow 8 oscillations of the GCs
along their orbits and the main findings are: i) clusters with an initial high
enough King concentration parameter (c>=1.2), preserve up to 50% of their
initial mass; ii) the inner density distribution of the survived clusters keep
a King model profile; iii) GC-GC collisions have a negligible effect with
respect to that caused by the passage through the galactic center; iv) the
orbital energy dissipation due to the tidal interaction is of the same order of
that caused by dynamical friction; v) complex sub-structures like "ripples" and
"clumps" formed, as observed around real clusters.
These findings support the validity of the hypothesis of merging of GCs in
the galactic central region, with modes that deserve further careful
investigations.Comment: LaTeX 2e, AASTeX v5.x, 23 pages with 14 figures. Accepted for
publication on the Astrophysical Journal. Final version with major change