Massive star and star cluster formation

Massive Star and Star Cluster Formation

I review the status of massive star formation theories: accretion from collapsing, massive, turbulent cores; competitive accretion; and stellar collisions. I conclude the observational and theoretical evidence favors the first of these models. I then discuss: the initial conditions of star cluster formation as traced by infrared dark clouds; the cluster formation timescale; and comparison of th...

Star Formation Efficiencies and Star Cluster Formation

Starbursts produce large numbers of Young Star Clusters (YSCs). Multi-color photometry in combination with a dedicated SED analysis tool allows to derive ages, metallicities, EB−V, and masses including 1σ uncertainties for individual clusters and, hence, mass functions for YSC systems. The mass function, known to be Gaussian for old Globular Cluster (GC) systems, is still controversial for YSC ...

Massive Star Formation

Star Cluster Formation and Star Formation: The Role of Environment and Star Formation Efficiencies

Analyzing global starburst properties in various kinds of starburst and post-starburst galaxies and relating them to the properties of the star cluster populations they form, I explore the conditions for the formation of massive, compact, long-lived star clusters. The aim is to find out whether the relative amount of star formation that goes into star cluster formation as opposed to field star ...

Equilibrium Star Cluster Formation

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...