Name: Mark Gieles
Institution: Utrecht University
University of Washington
Astrolunch
Title: The Effect of Spiral Arms on the Evolution of Star Clusters
Abstract:
In this study we use direct N-body simulations to investigate the effect
of spiral arms on the evolution of star clusters in disks.
The great sensitivity and resolution of the Hubble Space Telescope
made it possible to resolve individual extra-galactic star
clusters. This lead to the discovery of young massive clusters in
star burst galaxies and interacting galaxies, with an apparent similar
structure and morphology as the globular clusters seen in our Milky
Way. A key question is whether these young massive cluster populations
will evolve into an old population comparable to the globular cluster
population seen in the halo of almost every galaxy.
The internal evolution of star clusters has been studied quite
extensively and is pretty well understood. External perturbations,
however, may play a determining role in the evolution of
a star cluster. When in a disk, clusters experience a tidal
field, due to spiral arms. In grand design spiral galaxies, such as M51,
the arm/inter-arm density ratio can be of the order of 3-5. This is
comparable to the difference between the average density of the
cluster and its surroundings.
We study the effect of slow/fast passages through the spiral arms.
The slow passage close to corotation can lead to significant mass loss and
significant deformation of the cluster morphology, including the
formation of large tidal tails.
UW Astronomy Home Page
Colloquium Page