We report on the development, calibration, and refinement of the SDSS-I Value Added Catalog (VAC) of stellar abundances, temperatures, and surface gravities. This catalog is based on observations of several hundred thousand stars obtained during the course of the original Sloan Digital Sky Survey, now known as SDSS-I. A spectroscopic pipeline has

It is shown that the two-part minimum description length principle can be used to discriminate among different models that can explain a given observed data set. The description length is chosen to be the sum of the lengths of the message needed to encode the model plus the message needed to encode the data when the model is applied to the data set

Recent GLIMPSE data analysed by Benjamin et al. (2005) have further confirmed the hypothesis of the existence of an in-plane long bar that is different from the bulge of the Milky Way with the same characteristics that were emphasized some years ago by our team. In this contribution, we briefly discuss the published literature on the topic and

We present the K-correction for emission lines formed on the irradiated face of the companion stars in X-ray binaries. We compute this K-correction in a general approach as function of the mass ratio and the disc flaring angle. Our results combined with the detection of high energy emission lines arising from the donor star (e. g. Steeghs & Casares

The GTC is a 10.4m telescope being built in La Palma, Spain, by a consortium lead by the Instituto de Astrofisica de Canarias (IAC). Other members of the collaboration include Mexico and the University of Florida (US). The telescope is now complete, the main activity currently being the installation of the control system. This will lead to the

Aims.We investigate the flow field in the sunspot canopy using simultaneous Stokes vector spectropolarimetry of three sunspots (θ=27°, 50°, 75°) and their surroundings in visible (630.15 and 630.25 nm) and near infrared (1564.8 and 1565.2 nm) neutral iron lines. Methods: .To calibrate the Doppler shifts, we compare an absolute velocity calibration