Dynamical evolution of globular clusters in galaxies

TYPEAstrophysics Seminar
Speaker:Dr. Loren Hoffman
Affiliation:Hebrew University
Location:Lidow 620

Globular clusters (GCs) are believed to form in violent star formation episodes, where turbulence raises the Jeans mass far above the mass of the molecular clouds forming in the Milky Way today.  The GC systems of galaxies may therefore provide a fossil record of high-z starbursts associated with gas-rich mergers or "wild disks". However the present-day GC population is only a small relic of the young massive star cluster population at birth -- the "lucky survivors" that were not disrupted by the tidal fields of their host galaxies over the next Hubble time.  Current state-of-the-art treatments of GC disruption rely on direct N-body simulations that take months to run on special-purpose hardware.  I will present a new method for simulating GC evolution in a changing galactic tidal field, that combines a collisionless self-consistent field code with the Henon Monte Carlo technique for treating two-body relaxation.  This method can accurately evolve a 10^5-6 solar mass cluster for a Hubble time in a few days on the astrom cluster at HUJI.  I will also apply up-to-date semi-analytic models of GC destruction in a high-resolution simulation of the merging Antennae Galaxies, to show how the merger initial conditions and slow tidal evolution of the GCs imprint themselves on the long-term mass functions and kinematics of the GC system.