相关论文: NGC 1912 and NGC 1907: a close encounter between o…

We present the results of a self-consistent $N$-body simulation following the evolution of a primordial population of thick disc globular clusters (GCs). We study how the internal properties of such clusters evolve under the action of…

We describe Monte Carlo models for the dynamical evolution of the nearby globular cluster NGC 6397. The code includes treatments of two-body relaxation, most kinds of three- and four-body interactions involving primordial binaries and those…

In this study we use simulations of 128$^3$ particles to study the ellipticity and orientation of clusters of galaxies in N-body simulations of differing power-law initial spectra (P(k) \propto k^n ,n = +1, 0, -1, -2$), and density…

Star clusters - open and globulars - experience dynamical evolution on time scales shorter than their age. Consequently, open and globular clusters provide us with unique dynamical laboratories for learning about two-body relaxation, mass…

We present a new formation scenario for NGC2419, which is one of the most luminous,one of the most distant, and as well one of the most extended globular clusters of the Milky Way. We propose that NGC2419 is the remnant of a merged star…

Merging galaxy clusters allows to study the different mass components, dark and baryonic, separately. Also their occurrence enables to test the $\Lambda$CDM scenario and they could put constrains in the self interacting cross section of the…

The external destruction of protoplanetary discs in a clustered environment acts mainly due to two mechanisms: gravitational drag by stellar encounters and evaporation by strong stellar winds and radiation. If encounters play a role in disc…

The possible association of Galactic globular clusters with the Sgr Stream is shortly reviewed at the light of the most recent observations of the Stream. >= 20 % of the Galactic globular clusters with R_{GC}>= 10 Kpc are found to lie…

NGC 6791 is a unique stellar system among Galactic open clusters being at the same time one of the oldest open clusters and the most metal rich. Combination of its properties is puzzling and poses question of its origin. One possible…

Recently, observational data and high precision mapping of the local velocity field of Local Group and Virgo cluster have revealed a linear velocity-distance relation of the outermost galaxies, properly referred to as Local Hubble Flow. By…

M82 is the nearest starburst galaxy. It contains two large systems of super star clusters, one being spawned today in the active starforming core, and one produced by an earlier starburst event which coincided with the last orbital passage…

Most galaxies in the Universe are found in groups, which have various morphologies and dynamical states. Studying how groups evolve is an important step for our understanding in both large-scale structure formation and galaxy evolution. We…

We use direct N-body simulations to investigate the evolution of star clusters with large size-scales with the particular goal of understanding the so-called extended clusters observed in various Local Group galaxies, including M31 and…

Explaining the origin and evolution of exoplanetary "hot Jupiters" remains a significant challenge. One possible mechanism for their production is planet-planet interactions, which produces hot Jupiters from planets born far from their host…

The stars that populate the solar neighbourhood were formed in stellar clusters. Through N-body simulations of these clusters, we measure the rate of close encounters between stars. By monitoring the interaction histories of each star, we…

We have simulated the growth of structure in two 100 Mpc boxes for LCDM and SCDM universes. These N-body/SPH simulations include a gaseous component which is able to cool radiatively. A fraction of the gas cools into cold dense objects…

The study of the very young open cluster NGC 6231 clearly shows the presence of a mass segregation for the most massive stars. These observations, combined with those concerning other young objects and very recent numerical simulations,…

We have identified a few thousand star clusters in the nearby, late-type spiral galaxy M101, including approximately 90 candidate ancient globular clusters (GCs), from multi-band Hubble Space Telescope (HST) images. We obtained follow-up…

Close encounters and physical collisions between stars in young dense clusters may lead to the formation of very massive stars and black holes via runaway merging. We examine critically some details of this process, using N-body simulations…

We have obtained deep photometry of NGC 1199 (in the compact group HCG 22) and NGC 6868 (in the Telescopium loose group) with the Keck II and the VLT-I telescopes. Both galaxies are the optically brightest galaxy of their groups. NGC 1199…