We have performed fully self-consistent N -body simulations of star clusters near the Galactic center (GC). Such simulations have not been performed because it is the difficult to perform fast and accurate simulations of large-N systems using conventional methods. We used the Bridge code, which integrates the parent galaxy using the tree algorithm and the star cluster using the fourth-order Her...

Stars form with a complex and highly structured distribution. For a smooth star cluster to form from these initial conditions, the star cluster must erase this substructure. We study how substructure is removed using N-body simulations that realistically handle two-body relaxation. In contrast to previous studies, we find that hierarchical cluster formation occurs chiefly as a result of scatter...

We present near infrared J, H, and K images and K−band spectroscopy in the giant H II region W42. A massive star cluster is revealed; the color–color plot and K−band spectroscopic morphology of two of the brighter objects suggest the presence of young stellar objects. The spectrum of the bright central star is similar to unobscured stars with MK spectral types of O5–O6.5. If this star is on the...

The currently most popular models for the dynamical evolution of star clusters predict that the power-law Cluster Luminosity Functions (CLFs) of young star cluster systems will be transformed rapidly into the universal Gaussian CLFs of old Milky Way-type “globular” cluster systems. Here, we provide the first evidence for a turn-over in the intermediate-age, approximately 1 Gyr-old CLF in the ce...

We study the growth rate of stars via stellar collisions in dense star clusters, calibrating our analytic calculations with direct N-body simulations of up to 65536 stars, performed on the GRAPE family of computers. We find that star clusters with initial half-mass relaxation times < ∼ 20Myr are dominated by stellar collisions, the first collisions occurring at or near the point of core collaps...

This document gives a short status report on the cluster nder for online hit nding at STAR. The STAR DAQ/Level-3 system is designed to do the hit nding for the TPC online at an event rate of max. 100Hz. Currently two fast cluster nder exist using similar algorithms but diierent approaches and implementations to speed up execution on the used processor. This report will shortly explain the two a...