Equilibrium Star Cluster Formation
摘要
We argue that rich star clusters take at least several local dynamical times to form, and so are quasi-equilibrium structures during their assembly. Observations supporting this conclusion include morphologies of star-forming clumps, momentum flux of protostellar outflows from forming clusters, age spreads of stars in the Orion Nebula Cluster (ONC) and other clusters, and the age of a dynamical ejection event from the ONC. We show that these long formation timescales are consistent with the expected star formation rate in turbulent gas, as recently evaluated by Krumholz & McKee. Finally, we discuss the implications of these timescales for star formation efficiencies, the disruption of gas by stellar feedback, mass segregation of stars, and the longevity of turbulence in molecular clumps.
引用
@article{arxiv.astro-ph/0603278,
title = {Equilibrium Star Cluster Formation},
author = {Jonathan C. Tan and Mark R. Krumholz and Christopher F. McKee},
journal= {arXiv preprint arXiv:astro-ph/0603278},
year = {2009}
}
备注
5 pages, Accepted to ApJ Letters