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We present a study of beryllium (Be) abundances in a large sample of field solar-type dwarfs and sub-giants spanning a large range of effective temperatures. The Be abundances, computed using a very uniform set of stellar parameters and near-UV spectra obtained with 3 different instruments, are used to study the depletion of this light element. The

Classical model-atmosphere analyses of stellar spectra usually begin by measuring equivalent widths, and then proceed into a loop in which 1) model spectra are calculated for a set of abundances and atmospheric parameters, and 2) observed and computed spectra are compared and corrections to the abundances and parameters are inferred. Automated

The point spread function of a segmented aperture is seriously affected by the misalignment of the segments. Stringent requirements apply to position sensors and their calibration. The Active Phasing Experiment (APE) will be a technical instrument aimed at testing possible phasing techniques for a European Giant Optical Telescope (EGOT) in a

This paper presents a method to determine how much detail of the height stratification of atmospheric parameters can be retrieved from the inversion of spectral lines (and their polarization profiles, when available) via χ2-minimization algorithms. An a priori analysis of the response functions and their correlations permits an evaluation of the