Aims. The aim of this work is a detailed analysis of transit light curves from TrES-1 and TrES-2, obtained over a period of three to four years, in order to search for variabilities in observed mid-transit times and to set constraints on the presence of additional third bodies. Methods: Using the IAC 80 cm telescope, we observed transits of TrES-1

We study the evolution of galaxy structure and of the major merger fraction since z ˜ 1 to present in GOODS-S field for MB ≤ -20 and M* ≥ 1010 Msun selected galaxies. We segregate the galaxies into early-type galaxies (ET, E/S0/Sa), and late-type galaxies (LT, Sb-Irr) by their position in the concentration-asymmetry plane, while we pick up high

The AKARI and Spitzer satellites provided an unique opportunity to observe a variety of stars, which are considered as departing from the Asymptotic Giant Branch (AGB) and have started their post-AGB evolution recently. Most of these stars are absent optically and are bright in the mid-IR wavelength range. Spectra of close to 200 objects have been

We study the thermal (tSZ) and kinetic Sunyaev-Zel'dovich (kSZ) effect associated with superclusters of galaxies using the MareNostrum (MNU) universe smoothed particle hydrodynamics (SPH) simulation. In particular, we consider superclusters with characteristics (total mass, overdensity and number density of cluster members) similar to those of the

We present a general analytical formalism to calculate accurately several statistics related to underdense regions in the Universe. The statistics are computed for dark matter halo and galaxy distributions both in real space and redshift space at any redshift. Using this formalism, we found that void statistics for galaxy distributions can be

We present deep long-slit optical spectra for a sample of 36 ultraluminous infrared galaxies (ULIRGs), taken with the William Herschel Telescope on La Palma with the aim of investigating the star formation histories and testing evolutionary scenarios for such objects. Here we present the sample, the analysis techniques and a general overview of the