Related papers: Self-enrichment in globular clusters. I. An analyt…
Stars are often observed to form in clusters. It is therefore important to understand how such a region of concentrated mass is assembled out of the diffuse medium and its properties eventually prescribe the important physical mechanisms…
Galactic globular clusters consist of two main stellar populations, the pristine (1P) and polluted (2P) stars. The fraction of 1P stars in clusters, $F_{1P}$, is a decreasing function of the cluster present-day mass, $m_{prst}$. The…
We review recent work that investigates the formation of stellar clusters, ranging in scale from globular clusters through open clusters to the small scale aggregates of stars observed in T associations. In all cases, recent advances in…
Initial conditions for star formation in clusters are estimated for protostars whose masses follow the initial mass function (IMF) from 0.05 to 10 solar masses. Star-forming infall is assumed equally likely to stop at any moment, due to gas…
The presence and abundance of short lived radioisotopes (SLRs) $^{26}$Al and $^{60}$Fe in chondritic meteorites implies that the Sun formed in the vicinity of one or more massive stars that exploded as supernovae (SNe). Massive stars are…
We propose a self-consistent model for globular cluster formation in, but not limited to, our Galaxy, based on the merger model of Mathews and Schramm (1993). Stars and star clusters form in bursts at the merging interfaces as protogalactic…
Stars in star clusters are thought to form in a single burst from a common progenitor cloud of molecular gas. However, massive, old globular clusters -- with ages greater than 10 billion years and masses of several hundred thousand solar…
A stochastic model of the chemical enrichment of metal-poor systems by core-collapse (Type II) supernovae is presented, allowing for large-scale mixing of the enriched material by turbulent motions and cloud collisions in the interstellar…
We present color-magnitude diagrams of globular clusters for models with self-enrichment and pre-enrichment. The models with self-enrichment turn out to have two or more main sequence turnoff points in the color-magnitude diagram if the…
We consider the hypothesis that the formation of elliptical galaxies includes a phase in which star formation is mostly restricted to massive stars, with the bias towards high mass stars increasing with elliptical galaxy mass. The mass…
Young massive star clusters spanning $\sim 10^4 - 10^8 M_\odot$ in mass have been observed to have similar surface brightness profiles. Recent hydrodynamical simulations of star cluster formation have also produced star clusters with this…
Various galactic globular clusters display abundance anomalies that affect the morphology of their colour-magnitude diagrams. In this paper we consider the possibility of helium enhancement in the anomalous horizontal branch of NGC 2808. We…
Several scenarios have been proposed to explain the presence of multiple stellar populations in globular clusters. Many of them invoke multiple generations of stars to explain the observed chemical abundance anomalies, but it has also been…
Globular clusters formed in galactic mergers (e.g., The Antennae) can now be studied at different stages of their evolution. In young merger remnants (e.g., NGC 7252) these "second-generation" globulars appear by the hundreds as young halo…
Star formation is enhanced in spiral arms because of a combination of orbit crowding, cloud collisions, and gravitational instabilities. The characteristic mass for the instability is 10^7 Msun in gas and 10^5 Msun in stars, and the…
Star-to-star dispersion of r-process elements has been observed in a significant number of old, metal-poor globular clusters. We investigate early-time neutron-star mergers as the mechanism for this enrichment. Through both numerical…
Star formation is triggered in essentially three ways: (1) the pressures from existing stars collect and squeeze nearby dense gas into gravitationally unstable configurations, (2) random compression from supersonic turbulence makes new…
We present an end-to-end description of the formation process of globular clusters (GCs) which combines a treatment for their formation and dynamical evolution within galaxy haloes with a state-of-the-art semi-analytic simulation of galaxy…
Conditions for the fragmentation of expanding shells due to gravitational instability are discussed. The self-similar analytical solution is compared with the results of 3-dimensional computer simulations for the expansion into homogeneous…
Although globular clusters are generally chemically homogeneous, substantial abundance variations are sometimes seen even among unevolved main sequence stars, especially for the CNO group of elements. Multi-object intermediate-dispersion…