Multiple images of QSOs are formed when the gravitational field of an intervening galaxy bends the trajectories of the light rays. The granulation of the lens galaxy mass distribution (either in stars or compact dark matter objects) could induce non correlated variability between different images of the lensed QSO (microlensing). The relevance of

We have used the collisional broadening of neutral neon lines to determine the gas temperature of a microwave discharge at atmospheric pressure. The gas temperature can be obtained from the van der Waals broadening, provided that the Stark broadening is negligible. Thus, the variation of the Stark broadening of the Hbeta , Halpha , Hgamma lines has

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Recent studies of the substellar population in the Taurus cloud have revealed a deficit of substellar objects by a factor ≃ 2 compared to the Trapezium cluster population (Briceno et al. 1998; Luhman 2000). If confirmed, the higher low-mass cutoff in Taurus could have strong implications on IMF and substellar formation models. However, all studies

Theoretical considerations lead to the expectation that stars should not have masses larger than about m_{max*}=60-120M_&sun;, while the observational evidence has been ambiguous. Only very recently has a physical stellar mass limit near 150M_&sun; emerged thanks to modern high-resolution observations of local star-burst clusters. But this limit

Effective temperatures of 30 turnoff stars with -3.2 {[Fe/H]{ have been derived from the profiles of Balmer lines in high S/N, VLT/UVES spectra. While the systematic error of Teff may be of the order of 100K, the differential values of Teff are determined with a one-sigma precision of ˜25K. These precise Teff values are used in a study of the slope