Related papers: Evidence for Cluster to Cluster Variations in Low-…
Massive stars are strong sources of far-ultraviolet radiation that can be hostile to the evolution of protoplanetary disks, driving mass loss by external photoevaporation and shortening disk-dissipation timescales. Their effect may also…
We use published optical spectral and IR excess data from nine young clusters and associations to study the stellar mass dependent dispersal of circumstellar disks. All clusters older than ~3 Myr show a decrease in disk fraction with…
We perform a high resolution zoom-in simulation of star cluster assembly including the merger of two sub-clusters with initial conditions taken from previous large scale giant molecular cloud (GMC) simulations. We couple hydrodynamics to…
The high-energy radiation emitted by young stars can have a strong influence on their rotational evolution at later stages. This is because internal photoevaporation is one of the major drivers of the dispersal of circumstellar disks, which…
The regulation of angular momentum is one of the key processes for our understanding of stellar evolution. The rotational evolution of solar-mass stars is mainly determined by the magnetic interaction with their circumstellar disk and…
We study the structure and evolution of the very early protostellar disk (``protodisk'') just after protostar formation, where disk self-gravity dominates and the stellar contribution is dynamically minor. The disk redistributes angular…
We study the evolution of bound pairs of star clusters by means of direct N-body simulations. Our simulations include mass loss by stellar evolution. The initial conditions are selected to mimic the observed binary star cluster NGC 2136 and…
Context: The surface properties of rotating stars can vary from pole to equator, resulting in anisotropic stellar winds which are not included in the currently available evolutionary models. Aims: We develop a formalism to describe the mass…
We investigated the evolution of clusters of galaxies using self-consistent N-body simulations. We varied the initial model of galaxies and clusters, and studied the dependence of evolution on initial conditions. We found that the growth…
We use the EAGLE cosmological hydrodynamic simulation suite to study the specific angular momentum of galaxies, $j$, with the aims of (i) investigating the physical causes behind the wide range of $j$ at fixed mass and (ii) examining…
Here, I review some recent works on magnetism of cool, main-sequence stars, their winds and potential impact on surrounding exoplanets. The winds of these stars are very tenuous and persist during their lifetime. Although carrying just a…
We use N-body simulations to explore the influence of orbital eccentricity on the dynamical evolution of star clusters. Specifically we compare the mass loss rate, velocity dispersion, relaxation time, and the mass function of star clusters…
The evolution of rotating stars with zero-age main sequence (ZAMS) masses in the range 8 to 25 M_sun is followed through all stages of stable evolution. The initial angular momentum is chosen such that the star's equatorial rotational…
We present the results of a study aimed at assessing whether low and high mass stars form similarly. Our approach is (1) to examine the observed projected rotational velocities among a large sample of newly-formed stars spanning a range in…
Pre-main sequence evolutionary theory is not well-calibrated to observations. With care, the observed quantities can be converted into effective temperature and luminosity (i.e. the Hertzsprung-Russell diagram) which the theoretical…
The majority of observed mass-to-light ratios of globular clusters are too low to be explained by `canonical' cluster models, in which dynamical effects are not accounted for. Moreover, these models do not reproduce a recently reported…
We investigate the properties of the stellar populations of model galaxies as a function of galaxy evolutionary history and angular momentum content. We use the new semi-analytic model presented in Tonini et al. (2016). This new model…
Late-type main sequence stars exhibit an x-ray to bolometric flux ratio that depends on ${\tilde Ro}$, the ratio of rotation period to convective turnover time, as ${\tilde Ro}^{-\zeta}$ with $2\le \zeta \le 3$ for ${\tilde Ro} >0.13$, but…
Circumstellar discs are the precursors of planetary systems and develop shortly after their host star has formed. In their early stages these discs are immersed in an environment rich in gas and neighbouring stars, which can be hostile for…
The majority of stars form in a clustered environment. This has an impact on the evolution of surrounding protoplanetary discs (PPDs) due to either photoevaporation or tidal truncation. Consequently, the development of planets depends on…