We present a deep spectrophotometric mosaic of the Orion Nebula obtained with the Potsdam Multi-Aperture Spectrophotometer (PMAS) at Calar Alto Observatory. The aim of the observations has been to determine the spatial distribution of physical conditions and chemical abundances across the nebula and at different morphological structures. The 64

Among the distinguishing characteristics of the remarkable hot R Coronae Borealis star DY Centauri, which was recently found to be a spectroscopic binary, is the presence of nebular forbidden lines in its optical spectrum. A compilation of photometry from 1970 to the present suggests that the star has evolved to higher effective temperatures. A

We present a sample of the most massive galaxies (M^{*}>10^{11}{M}_{&sun;}) found at z=0 in a fully cosmological simulation performed with MASCLET (Mesh Adaptative Scheme for CosmologicaL structurE evoluTion). te{quilis04} The Upper (lower) pannel shows the merger (quiet) galaxies depending on elipticity (ɛ) and velocity vs velocity-dispersion (v/σ

We present the first results of a program aimed to study the stellar populations of moderate luminosity X-ray selected Active Galactic Nuclei (AGN) at intermediate redshifts. We use observations taken as part of the Survey for High-z Absorption Red and Dead Sources (SHARDS) with the optical instrument OSIRIS on the 10.4m Gran Telescopio Canarias

The study of small scale magnetic structures in the solar photosphere is of great relevance for the understanding of the global behaviour of the Sun. Because of the small spatial and temporal scales involved, the use of high resolution images and fast cadence is fundamental for their study. In order to obtain such images, sophisticated

We introduce a new automatic code (StePar) for determinig stellar atmospheric parameters (T_{eff}, log{g}, ξ and [Fe/H]) in an automated way. StePar employs the 2002 version of the MOOG code (Sneden 1973) and a grid of Kurucz ATLAS9 plane-paralell model atmospheres (Kurucz 1993). The atmospheric parameters are obtained from the EWs of 263 Fe I and