Numerical simulations of globular cluster formation

We examine various physical processes associated with the formation of glob ular clusters by using the three-dimensional smoothed particle hydrodynamic s (SPH) code. Our code includes radiative cooling of gases, star formation, energy feedback by stars including stellar winds and supernovae, and chemi cal enrichment by stars. We assume that, in the collapsing galaxy, isotherm al cold clouds form through thermal condensations and become proto-globular clouds. We calculate the size of proto-globular clouds by solving the line arized equations for perturbation. We compute the evolution of the inner re gion of the protocloud with our SPH code for various initial radius and ini tial composition of gases. When the initial gases contain no heavy elements , the evolution of protoclouds sensitively depends on the initial radius. F or a smaller initial radius, the initial starburst is so intense that the s ubsequent star formation occurs in the central regions to form a dense star cluster as massive as the globular cluster. When the initial gases contain some heavy elements, the metallicity of gases affects the evolution and th e final stellar mass. If the initial radius of the proto-globular clouds wa s relatively large, the formation of a star cluster as massive as the globu lar clusters requires the initial metallicity as high as [Fe/H-2] greater t han or equal to -2. The self-enrichment of heavy elements in the star clust er does not occur in all cases.