EN EL TRABAJO SE HA DETERMINADO LA ABUNDANCIA DE OXIGENO EN 43 ESTRELLAS ENANAS POBRES EN METALES PERTENECIENTES AL HALO Y DISCO GALACTICO A PARTIR DE ESPECTROS DE ALTA RESOLUCIO. LAS OBSERVACIONES SE REALIZARON EN EL TELESCOPIO ISAAC NEWTON DE 2.5 M, UTILIZANDO EL ESPECTROGRAFO DE DISPERSION INTERMEDIA Y DETECTORES CCD. SE HA ENCONTRADO QUE LA

Not Available

In its most general acceptation, surface photometry is a technique applicable to any "extended" object, irrespective of the spectral band of the observational frame. The subject of this paper is restricted to the mapping of galaxies in the "standard" bands of the visible. By combining CCD images with deep large-field photographs, this technique

The influence of rotation and finite size of the radiation source on the orbits of dust particles around stars is analyzed. It is found that there are physical situations in which the results first derived by Robertson (Poynting-Robertson effect), corresponding to a nonrotating point-like source, cannot properly describe the dynamical behavior of

Not Available

Not Available