We present the first results of an ambitious work still in progress. We are modeling the light distribution of a large sample (˜10000) of cluster galaxies from the WINGS survey as single Sérsic or bulge plus disk systems. Our classification scheme is based on a logical filter that takes advantage of well-known characteristics of these two kinds of

We use measurements of the projected galaxy correlation function wp(rp) and galaxy void statistics to test whether the galaxy content of halos of fixed mass is systematically different in low-density environments. We present new measurements of the void probability function (VPF) and underdensity probability function (UPF) from Data Release 4 of

Context: The recent discovery of a group of trans-neptunian objects (TNOs) in a narrow region of the orbital parameter space and with surfaces composed of almost pure water ice, being 2003 EL{61} its largest member, promises new and interesting results about the formation and evolution of the TNb and the outer Solar System. Aims: The aim of this

We report the discovery of two previously unseen X-ray sources detected in a 5ks Chandra/ACIS observation starting on 2008-10-13.15 UT as part of our ongoing Chandra/HST M31 transient program. Due to the low number of counts, no detailed spectral analysis was possible. The spectra were modelled with an absorbed power law of nH = 6.67e20 atoms/ cm2

The surface-brightness profiles of galaxy disks fall into three main classes, based on whether they are simple exponentials (Type I), bend down at large radii (Type II, `truncations') or bend up at large radii (Type III, `antitruncations'). Here, we discuss how the frequency of these different profiles depends on Hubble type, environment, and the

At present, ten years after they were first discovered, ten accreting millisecond pulsars are known. I present a study of the aperiodic X-ray variability in three of these systems, which led to the discovery of simultaneous kHz quasi periodic oscillations in XTE J1807-294 and extremely strong broadband noise at unusually low variability frequencies