相关论文: Evolution of two stellar populations in globular c…
The evolution of star clusters is determined by several internal and external processes. Here we focus on two dominant internal effects, namely energy exchange between stars through close encounters (two-body relaxation) and mass-loss of…
The residual gas within newly formed star clusters is expelled through stellar feedback on timescales ~ 1 Myr. The subsequent expansion of the cluster results in an unbinding of a fraction of stars before the remaining cluster members can…
We investigate the response of initially substructured, young, embedded star clusters to instantaneous gas expulsion of their natal gas. We introduce primordial substructure to the stars and the gas by simplistically modelling the star…
We use direct $N$-body calculations to investigate the impact of primordial mass segregation on the size scale and mass-loss rate of star clusters in a galactic tidal field. We run a set of simulations of clusters with varying degrees of…
We briefly summarize the impact of the chemical peculiarities associated to the multiple population phenomenon in Galactic Globular Clusters, on the evolutionary properties and spectral energy distribution of second generation stars, in…
The ability of young stellar clusters to expel or retain the gas left over after a first episode of star formation is a central issue in all models aiming to explain multiple stellar populations and the peculiar light element abundance…
The picture of the early evolution of globular clusters has been significantly revised in recent years. Current scenarios require at least two generations of stars of which the first generation (1G), and therefore also the protocluster…
We perform a series of direct $N$-body calculations to investigate the effect of residual gas expulsion from the gas-embedded progenitors of present-day globular clusters (GCs) on the stellar mass function (MF). Our models start either…
We examine the effects of gas expulsion on initially sub-structured and out-of-equilibrium star clusters. We perform $N$-body simulations of the evolution of star clusters in a static background potential before removing that potential to…
Our arguments deal with the early evolution of Galactic globular clusters and show why only a few of the supernovae products were retained within globular clusters and only in the most massive cases ($M \ge 10^6$ Msol), while less massive…
Most globular clusters (GCs) show evidence for multiple stellar populations, suggesting the occurrence of several distinct star-formation episodes. The large fraction of second population (2P) stars observed requires a very large 2P gaseous…
We present the results of Monte Carlo simulations aimed at exploring the evolution towards energy equipartition of first- (1G) and second-generation (2G) stars in multiple-population globular clusters and how this evolution is affected by…
We present the result of a survey of Monte Carlo simulations of globular clusters hosting two generations of stars including a large (f_b=50%) fraction of primordial binaries in both populations. The dynamical evolution of the two stellar…
Star clusters are observed to form in a highly compact state and with low star-formation efficiencies. If the residual gas is expelled on a dynamical time the clusters disrupt thereby (i) feeding a hot kinematical stellar component into…
The paper deals with the conditions required to form at least two stellar generations in globular clusters under the constraints generated by feedback from massive stars as well as radiative cooling and the metallicity of the primordial…
Nearly all globular clusters (GCs) studied to date show evidence for multiple stellar populations, in stark contrast to the conventional view that GCs are a mono-metallic, coeval population of stars. Building on earlier work, we propose a…
By means of grid-based, 3D hydrodynamical simulations we study the formation of second generation (SG) stars in a young globular cluster (GC) of mass 10^7 Msun, the possible progenitor of an old GC with a present mass ~(1-5) * 10^6 Msun.…
We study the evolution of embedded clusters. The equations of motion of the stars in the cluster are solved by direct N-body integration while taking the effects of stellar evolution and the hydrodynamics of the natal gas content into…
By adopting the empirical constraints related to the estimates of Helium enhancement ($\Delta Y$), present mass ratio between first and second stellar generations ($M_{1G}/M_{2G}$) and the actual mass of Galactic globular clusters…
Stars mostly form in groups consisting of a few dozen to several ten thousand members. For 30 years, theoretical models provide a basic concept of how such star clusters form and develop: they originate from the gas and dust of collapsing…