We simulate the characteristics of the Galactic population of radio and gamma-ray pulsars using Monte Carlo techniques. At birth, neutron stars are spatially distributed with supernova-kick velocities in the Galactic disk and randomly dispersed in age back to 109 years. They are evolved in the Galactic gravitational potential to the present time

Our conception of galaxy evolution inside clusters have recently changed due to an increasing evidence suggesting a pre-processing of galaxies at moderate densities. Based on the high frequency of interacting systems found at intermediate densities, we use the SDSS-DR4 data to analyse the role of close galaxy interactions as environmental

We explore the stability of different galaxy light concentration indices as a function of the outermost observed galaxy radius. With a series of analytical light-profile models, we show mathematically how varying the radial extent to which one measures a galaxy's light can strongly affect the derived galaxy concentration. The ``mean concentration

Numerical simulations predict that gas accretion from the cosmic web drives star formation in disks galaxies. The process is important in low mass haloes ( 1012 M⊙), therefore, in the early universe when galaxies were low mass, but also in dwarf galaxies of the local universe. The gas that falls in is predicted to be tenuous, patchy, partly ionized

Simultaneous modeling of the line and continuum emission from the nuclear region of the Circinus galaxy is presented. Composite models that include the combined effect of shocks and photoionization from the active center and from the circumnuclear star-forming region are considered. The effects of dust reradiation, bremsstrahlung from the gas, and

Context. The recently discovered bipolar outflow Ou4 has a projected size of more than one degree in the plane of the sky. It is apparently centred on the young stellar cluster - whose most massive representative is the triple system HR 8119 - inside the H ii region Sh 2-129. The driving source, the nature, and the distance of Ou4 are not known