New measurements of the velocity dispersion of the globular cluster ω Centauri allow us to trace its gravitational potential down to an acceleration of 8×10-9 cm s-2. It is found that the dispersion profile remains flat well inside the tidal radius as soon as the acceleration of gravity approaches a_0, a result that finds its simplest explanation

Knowledge of vertical structure of the turbulence in a site is an essential input for the requirements, performances and operation of Adaptive Optics systems. The statistics of the turbulence intensity and the coherence time of the layers affect the complexity of the design and implementation of a particular MCAO system. On the other hand, the

Esta tesis presenta el desarrollo de una serie de métodos y técnicas para resolver problemas de transporte radiativo en líneas moleculares y su aplicación en algunos campos de investigación en astrofísica molecular. Por ejemplo, investigamos la formación de las líneas rotacionales de agua en el complejo molecular gigante SgrB2, la formación de las

BL Lacertae has been the target of four observing campaigns by the Whole Earth Blazar Telescope (WEBT) collaboration. In this paper we present UBVRI light curves obtained by the WEBT from 1994 to 2002, including the last, extended BL Lac 2001 campaign. A total of about 7500 optical observations performed by 31 telescopes from Japan to Mexico have

The use of alternative energies is becoming common in many places around the world. It is envisaged that most large projects will consider the use of alternative energies in this new century. Such use or at least the attempts to use renewable energies to somewhat offset the power requirements of an ELT will be seen very positively by the general

We present the values of CN and Mg overabundances with respect to Fe, for early-type galaxies in 8 clusters over a range of richness and morphology. Spectra were taken from the Sloan Digital Sky Survey (SDSS) DR1 spectroscopic database, and from WHT and CAHA observations. Abundances were derived from absorption lines and single burst population