This work quantifies the influence of the terrestrial atmosphere on the instrumental polarization (IP) of telescopes. Our numerical simulations show that seeing mostly induces a random crosstalk between Stokes parameters. The main contamination affects the linear polarization signals and is due to mixing with intensity. In general, circular

HH 262 is a group of emitting knots displaying an `hour-glass' morphology in the Hα and [SII] lines, located 3.5 arcmin to the north-east of the young stellar object L1551-IRS5, in Taurus. We present new results of the kinematics and physical conditions of HH 262 based on Integral Field Spectroscopy covering a field of ~1.5 × 3 arcmin2, which

Integral field optical spectroscopy with the INTEGRAL fiber-based system is used to map the extended ionized regions and gas flows in Mrk 273, one of the closest ultraluminous infrared galaxies. The Hβ and [O III] λ5007 maps show the presence of two distinct regions separated by 4" (3.1 kpc) along position angle (P.A.) 240 deg. The northeastern

We analyze a time series of high angular resolution magnetograms of quiet Sun Inter-Network (IN) magnetic fields. These magnetograms have a spatial resolution better than 0farcs5, a noise of some 20 G, and they have been obtained at the disk center during the minimum of the solar cycle. The IN regions show a typical unsigned flux density of the

We investigate the influence of interactions on the star formation by studying a sample of almost 1500 of the nearest galaxies, all within a distance of ˜45 Mpc. We define the massive star formation rate (SFR), as measured from far-IR emission, and the specific star formation rate (SSFR), which is the former quantity normalized by the stellar mass

We present the main results of the Ph.D. thesis carried out by López-Sánchez (Ph.D. thesis, 2006), in which a detailed morphological, photometric and spectroscopic analysis of a sample of 20 Wolf-Rayet (WR) galaxies was performed. The main aims are the study of the star formation and O and WR stellar populations in these galaxies, and the role that