As most if not all stars are born in stellar clusters the shape of the mass function of the field stars is not only determined by the initial mass function of stars (IMF) but also by the cluster mass function (CMF). In order to quantify this Monte-Carlo simulations were carried out by taking cluster masses randomly from a CMF and then populating these clusters with stars randomly taken from an ...

The analysis of a sample of 52 clusters with precise and hypothesis-parsimonious measurements of mass, derived from caustics based on about 208 member velocities per cluster on average, shows that low-mass clusters and groups are not simple scaled-down versions of their massive cousins in terms of stellar content: lighter clusters have more stars per unit cluster mass. The same analysis also sh...

Active Galactic Nuclei can produce extremely powerful jets. While tightly collimated, the scale of these jets and the stellar density at galactic centers implies that there will be many jet/star interactions, which can mass-load the jet through stellar winds. Previous work employed modest wind mass outflow rates, but this does not apply when mass loading is provided by a small number of high ma...

We use very deep near-infrared (NIR) imaging data obtained in MOIRCS Deep Survey (MODS) to investigate the evolution of the galaxy stellar mass function back to z ∼ 3. The MODS data reach J = 24.2, H = 23.1, K = 23.1 (5σ, Vega magnitude) over 103 arcmin (wide) and J = 25.1, H = 23.7, K = 24.1 over 28 arcmin (deep) in the GOODS-North region. The wide and very deep NIR data allow us to measure th...

Using the publicly available VESPA database of SDSS Data Release 7 spectra, we calculate the stellar Mass Weighted Age (hereafter MWA) as a function of local galaxy density and dark matter halo mass. We compare our results with semi-analytic models from the public Millennium Simulation. We find that the stellar MWA has a large scatter which is inherent in the data and consistent with that seen ...