Related papers: Oort Cloud Formation and Evolution in Star Cluster…
The size distribution and total mass of objects in the Oort Cloud have important implications to the theory of planets formation, including the properties of, and the processes taking place in the early solar system. We discuss the…
In this paper, we focus on ram-pressure stripping and evaporation of disk galaxies in and around a cluster. We show that the evolution of the disk surface density affects the efficiency of ram-pressure stripping of galaxies at z>~1. We also…
We examine the growth of the stellar content of galaxies from z=3-0 in cosmological hydrodynamic simulations incorporating parameterised galactic outflows. Without outflows, galaxies overproduce stellar masses (M*) and star formation rates…
Recent surveys of star forming regions have shown that most stars, and probably all massive stars, are born in dense stellar clusters. The mechanism by which a molecular cloud fragments to form several hundred to thousands of individual…
We study how the proportion of star-forming galaxies evolves between z=0.8 and z=0 as a function of galaxy environment, using the [OII] line in emission as a signature of ongoing star formation. Our high-z dataset comprises 16 clusters, 10…
We study the evolution of star clusters in the Galactic tidal field starting from their birth in molecular clumps. Our model clusters form according to the local-density-driven cluster formation model in which the stellar density profile is…
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…
Using direct $N$-body simulations, we investigate the initial conditions and evolution of a star-forming region resembling the Orion Nebula Cluster (ONC) with the advanced \textsc{NBODY6} code. By varying the initial conditions, we aim to…
We report the first results of a research program to explore the sensitivity of the orbits of Oort cloud comets to changes in the strength of the Galactic tides in the plane of the disk and also to changes in the mass of the host star. We…
Starting from planetary systems with three giant planets and an outer disk of planetesimals, we use dynamical simulations to show how dynamical instabilities can transform planetesimal disks into 100-1000 AU-scale isotropic clouds. The…
We present a numerical study of the evolution of molecular clouds, from their formation by converging flows in the warm ISM, to their destruction by the ionizing feedback of the massive stars they form. We improve with respect to our…
Recent numerical simulations have shown that the unstable disk within the central regime of the primordial gas cloud fragments to form multiple protostars on several scales. Their evolution depends on the mass accretion phenomenon,…
The complete sample of large-perihelion nearly-parabolic comets discovered during the period 1901-2010 is studied starting from their orbit determination. Next, an orbital evolution that includes three perihelion passages…
Observations of the dust and gas around embedded stellar clusters reveal some of the processes involved in their formation and evolution. Large scale mass infall with rates dM/dt=4e-4 solar masses/year is found to be disrupted on small…
Galaxies infalling into clusters undergo both star-formation quenching and morphological transformation due to environmental effects. We investigate these processes and their timescales using a local sample of 20,191 cluster and 11,674…
Observations and theory both suggest that star clusters form sub-virial (cool) with highly sub-structured distributions. We perform a large ensemble of N-body simulations of moderate-sized (N=1000) cool, fractal clusters to investigate…
We have performed N-body simulations of tidally filling star clusters with a range of orbits in a Milky Way-like potential to study the effects of orbital inclination and eccentricity on their structure and evolution. At small…
A star with main sequence mass greater than $25\sim 30\msun$ may collapse to a black hole of about 10 $\msun$ at the final stage of the evolution. About an order of 1\% of stellar mass is likely to be in form of such black holes in…
The evolution of protostellar outflows is investigated under different mass accretion rates in the range $\sim10^{-5}-10^{-2} {\rm M}_\odot$ yr$^{-1}$ with three-dimensional magnetohydrodynamic simulations. A powerful outflow always appears…
Observations indicate that in young stellar clusters the binary fraction for massive stars is higher than for solar mass stars. For the Orion Nebula Cluster (ONC) there is a binary frequency of ~ 50% for solar-mass stars compared to 70-100%…