We investigate environmental effects on evolution of cluster galaxies under hierarchical structure formation scenario using combination of a dissipationless N-body simulation and a semi-analytic model of galaxy formation. The N-body simulation enables us to calculate orbits of galaxies in simulated clusters. Therefore we can include stripping of cold gas from the galactic disks by ram pressure ...

Stars form in embedded star clusters which play a key role in determining the properties of a galaxy’s stellar population. A large fraction of newly born massive stars are shot out from dynamically unstable embedded-cluster cores spreading them to large distances before they explode. Embedded clusters blow out their gas once the feedback energy from the new stellar population overcomes its bind...

Q1 We discuss images of the central 10 kpc (in projection) of the galaxy merger NGC 6240 at H and K 0 bands, taken with the NIRC2 narrow camera on Keck II using natural guide star adaptive optics. We detect 28 star clusters in the NIRC2 images, of which only 7 can be seen in the similar spatial resolution, archival WFPC2 Planetary Camera data at either B or I band. Combining the NIRC2 narrow ca...

We present a preliminary study of the star formation distribution within three Virgo Cluster galaxies using the 24 μm Spitzer observations from the Spitzer Survey of Virgo (SPITSOV) in combination with Hα observations. The purpose of our study is to explore the relationship between the star formation distribution within galaxies and the type (and phase) of interactions experienced within the cl...

The disruptive effect of galactic tides is a textbook example of gravitational dynamics. However, depending on the shape of the potential, tides can also become fully compressive. When that is the case, they might trigger or strengthen the formation of galactic substructures (star clusters, tidal dwarf galaxies), instead of destroying them. We perform N -body simulations of interacting galaxies...

Interacting galaxies favour the formation of star clusters but are also suspected to affect their evolution through an intense and rapidly varying tidal field. Treating this complex behaviour remains out-of-reach of (semi-)analytical studies. By computing the tidal field from galactic models and including it into star-by-star N-body simulations of star clusters, we monitor the structure and mas...

The stellar initial mass functions (IMFs) for the Galactic bulge, the Milky Way, other galaxies, clusters of galaxies, and the integrated stars in the Universe are composites from countless individual IMFs in star clusters and associations where stars form. These galaxy-scale IMFs, reviewed in detail here, are not steeper than the cluster IMFs except in rare cases. This is true even though low ...

Over the past years observations of young and populous star clusters have shown that the stellar IMF appears to be an invariant featureless Salpeter power-law with an exponent α = 2.35 for stars more massive than a few M⊙. A consensus has also emerged that most, if not all, stars form in stellar groups and star clusters, and that the mass function of young star clusters in the solar-neighborhoo...