Related papers: Was The Sun Born In A Massive Cluster?
Most stars are born in dense stellar environments where the formation and early evolution of planetary systems may be significantly perturbed by encounters with neighbouring stars. To investigate on the fate of circumstellar gas disks and…
We investigate the possibility that the Sun could have been born in M67 by carrying out $N$-body simulations of M67-like clusters in a time-varying Galactic environment, and following the galactic orbits of stars that escape from them. We…
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…
Their ubiquity and extreme densities make star clusters probes of prime importance of galaxy evolution. Old globular clusters keep imprints of the physical conditions of their assembly in the early Universe, and younger stellar objects,…
ALMA observations of the Serpens South star-forming region suggest that stellar protoclusters may be completely mass segregated at birth. Independent observations also suggest that embedded clusters form segregated by mass. As the…
The masses of star clusters range over seven decades, from ten up to one hundred million solar masses. Remarkably, clusters with masses in the range 10^4 to 10^6 solar mases show no systematic variation of radius with mass. However, recent…
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,…
This paper considers the lithopanspermia hypothesis in star forming groups and clusters, where the chances of biological material spreading from one solar system to another is greatly enhanced (relative to the field) due to the close…
A debris disk is a constituent of any planetary system surrounding a main sequence star. We study whether close stellar encounters can disrupt and strip a debris disk of its planetesimals in the expanding open cluster of its birth with a…
At least 10-15% of nearby sun-like stars have known Jupiter-mass planets. In contrast, very few planets are found in mature open and globular clusters such as the Hyades and 47 Tuc. We explore here the possibility that this dichotomy is due…
Star formation is triggered in essentially three ways: (1) the pressures from existing stars collect and squeeze nearby dense gas into gravitationally unstable configurations, (2) random compression from supersonic turbulence makes new…
Most stars, binaries, and higher multiplicity systems are thought to form in stellar clusters and associations, which later dissociate. Very wide binaries can be easily disrupted in clusters due to dynamical evaporation (soft binaries)…
Most stars form in clusters where relatively close encounters with other stars are common and can leave imprints on the orbital architecture of planetary systems. In this paper, we investigate the inclination excitation of debris disk…
Some young star clusters show a degree of mass segregation that is inconsistent with the effects of standard two-body relaxation from an initially unsegregated system without substructure, in virial equilibrium, and it is unclear whether…
We present a simple analytical description of the disruption of star clusters in a tidal field, which agrees excellently with detailed N-body simulations. The analytic expression can be used to predict the mass and age histograms of…
Some of the most massive globular clusters of our Milky Way, such as for example omega-Centauri, show a mixture of stellar populations spanning a few Gyr in age and 1.5 dex in metallicities. In contrast, standard formation scenarios predict…
Clusters are the dense inner regions of a wide-spread hierarchy of young stellar structures. They often reveal a continuation of this hierarchy inside of them, to smaller scales, when they are young, but orbital mixing eventually erases…
We present a new study of the collisional runaway scenario to form an intermediate-mass black hole (IMBH, MBH > 100 Msun) at the centre of a young, compact stellar cluster. The first phase is the formation of a very dense central core of…
We investigate the formation of both clustered and distributed populations of young stars in a single molecular cloud. We present a numerical simulation of a 10,000 solar mass elongated, turbulent, molecular cloud and the formation of over…
We discuss the structural change and degree of mass segregation of young dense star clusters within about 100pc of the Galactic center. In our calculations, which are performed with GRAPE-6, the equations of motion of all stars and binaries…