Аннотация
We perform the largest currently available set of direct N-body calculations
of young star cluster models to study the dynamical influence, especially
through the ejections of the most massive star in the cluster, on the current
relation between the maximum-stellar-mass and the star-cluster-mass. We vary
several initial parameters such as the initial half-mass radius of the cluster,
the initial binary fraction, and the degree of initial mass segregation. Two
different pairing methods are used to construct massive binaries for more
realistic initial conditions of massive binaries. We find that lower mass
clusters (<= 10^2.5 Msun) do not shoot out their heaviest star. In the case of
massive clusters (>= 1000 Msun), no most-massive star escapes the cluster
within 3 Myr regardless of the initial conditions if clusters have initial
half-mass radii, r_0.5, >= 0.8 pc. However, a few of the initially smaller
sized clusters (r_0.5 = 0.3 pc), which have a higher density, eject their most
massive star within 3 Myr. If clusters form with a compact size and their
massive stars are born in a binary system with a mass-ratio biased towards
unity, the probability that the mass of the most massive star in the cluster
changes due to the ejection of the initially most massive star can be as large
as 20 per cent. Stellar collisions increase the maximum-stellar-mass in a large
number of clusters when clusters are relatively dense (M_ecl >= 10^3 Msun and
r_0.5 = 0.3 pc) and binary-rich. Overall, we conclude that dynamical effects
hardly influence the observational maximum-stellar-mass -- cluster mass
relation.
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