Related papers: Formation and evolution of clumpy tidal tails arou…
As a stellar group forms within its parent molecular cloud, new members first appear in the deep interior. These overcrowded stars continually diffuse outward to the cloud boundary, and even beyond. Observations have so far documented only…
Recent progress in studies of globular clusters has shown that they are not simple stellar populations, being rather made of multiple generations. Evidence stems both from photometry and spectroscopy. A new paradigm is then arising for the…
The surroundings of globular clusters in the outer halo are one of the best places to look for the remnants of ancient dwarf satellites. The classical Searle & Zinn (1978) scenario of the formation of the Milky Way, in which the halo…
A kinematical analysis applied to a sample of galaxy clusters indicates that the differences between the velocity distribution of elliptical and spiral galaxies are associated with the shape of their orbit families. The orbital anisotropies…
We investigate pulsar timing residuals due to the coupling effect of the pulsar transverse acceleration and the R$\rm{\ddot{o}}$mer delay. The effect is relatively small and usually negligible. Only for pulsars in globular clusters, it is…
This review focuses on how galaxies and their globular cluster systems form. I first discuss the now fairly convincing evidence that some globular clusters form in galaxy starbursts/mergers. One way these observations are valuable is they…
We discuss the fragmentation of a filamentary cloud on the basis of a 1-dimensional hydrodynamical simulation of a self-gravitating gas cloud. The simulation shows that dense cores are produced with a semi-regular interval in space and time…
Absolute proper motions for six new globular clusters have recently been determined. This motivated us to obtain the Galactic orbits of these six clusters both in an axisymmetric Galactic potential and in a barred potential, such as the one…
We present Gemini optical spectroscopy of three young star clusters in the western tidal tail of NGC3256. Compact star clusters (as opposed to dwarf-galaxy candidates) in tidal tails are rare, with these three clusters the first for which…
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…
Globular clusters are large and dense agglomerate of stars. At variance with smaller clusters of stars, they exhibit signs of some chemical evolution. At least for this reason, they are intermediate between open clusters and massive objects…
The kinematical and spatial properties of the metal-rich globular clusters in the Galaxy ([Fe/H] > -0.8) indicates that these objects do not comprise a homogeneous population. Three subsystems are identified. The highest-mass clusters…
The Milky Way contains several distinct old stellar components that provide a fossil record of its formation. We can understand their spatial distribution and kinematics in a hierarchical formation scenario by associating the proto-galactic…
The isothermal gravitational collapse and fragmentation of a molecular cloud region and the subsequent formation of a protostellar cluster is investigated numerically. The clump mass spectrum which forms during the fragmentation phase can…
As an open cluster orbits the Milky Way, gravitational fields distort it, stripping stars from the core and forming tidal tails. Recent work has identified tidal tails of the Praesepe cluster; we explore rotation periods as a way to confirm…
The dynamics of a close binary system of globular clusters is considered. It is shown that the star transfer process from one of the components to the other should lead to the decrease of dimension of the first cluster with simultaneous…
Recent progress in the understanding of star formation is summarized. A consistent picture is emerging where molecular clouds form with turbulent velocity fields and clumpy substructure, imprinted already during their formation. The clouds…
We describe a scheme for the formation of globular cluster systems in early-type galaxies using a semi-analytic model of galaxy formation. Operating within a Lambda CDM cosmology, we assume that metal-poor globular clusters are formed at…
Core radii of globular clusters in the Large and Small Magellanic Clouds show an increasing trend with age. We propose that this trend is a dynamical effect resulting from the accumulation of massive stars and stellar-mass black holes at…
Recent observations show that small, young, stellar groupings of ~10 to 40 members tend of have a centrally-located most massive member, reminiscent of mass segregation seen in large clustered systems. Here, we analyze hydrodynamic…