Globular cluster simulations by MOCCA code
Abstract
Description
The MOCCA code is one of the most advanced codes that has the capacity to
simulate a realistic sized star cluster with a full dynamical history including stellar
evolution using Monte Carlo methods for the cluster evolution and the Fewbody
code for scattering. The dynamical evolution of a cluster can result in the
formation of many binary systems. Some of these binaries may be very close.
Close double white dwarf binaries (double WDBs) may be promising gravitational
wave sources.
Our work uses MOCCA to simulate 90 globular clusters with different numbers of
stars, binary fractions, metallicities and power-law indices of the initial mass
function. After ruling out models which evaporate before 9 Gyrs and uninteresting
models with very low numbers of WDBs, we do multiple runs of the remaining
models for around a Hubble time in order to get statistics on the overall WDB
populations of different component types, orbital periods and cluster radius in the
time range from 8 Gyrs to 10 Gyrs. We consider WDBs that exist within a
specified time range & Lagrangian radius range and have orbital periods less than
a day to be observable. Thus we set up a map of possible WDB detection rates for
different types of globular clusters.
PDF; 77 pgs.
PDF; 77 pgs.