Simulations of Nuclear Cluster formation

TL;DR

This study uses detailed N-body simulations to explore how globular clusters interact and merge in galactic centers, supporting the idea that such processes can form nuclear clusters.

Contribution

It provides a fully self-consistent simulation demonstrating the decay and merging of globular clusters, with new insights into timescales and stability of nuclear clusters.

Findings

Frictional orbital decay is twice as fast as Chandrasekhar's prediction.

Progenitor clusters merge in less than 20 galactic core-crossing times.

Nuclear cluster remains quasi-stable for at least 70 core-crossing times.

Abstract

Preliminary results are presented about a fully self-consistent N-body simulation of a sample of four massive globular clusters in close interaction within the central region of a galaxy. The N-body representation (with N=1.5x10^6 particles in total) of both the clusters and the galaxy allows to include in a natural and self-consistent way dynamical friction and tidal interactions. The results confirm the decay and merging of globulars as a viable scenario for the formation/accretion of compact nuclear clusters. Specifically: i) the frictional orbital decay is about 2 times faster than that predicted by the generalized Chandrasekhar formula; ii) the progenitor clusters merge in less than 20 galactic core-crossing time; iii) the NC configuration keeps a quasi-stable state at least within 70 galactic core-crossing times.