We have obtained adaptive optics images and accurate radial velocities for 7 very low mass objects, In the course of a long term effort to determine accurate...

We present improved visual and near-infrared empirical mass-luminosity relations for very low mass stars (M

The Ca II H and K lines are among the few features available to infer the metallicity of extremely metal-poor stars from medium-resolution spectroscopy...

Context. Measurable linear scattering polarization signals have been predicted and detected at the solar disk center in the cores of chromospheric lines. These...

Context. The star HD 52265 is a G0V metal-rich exoplanet-host star observed in the seismology field of the CoRoT space telescope from November 2008 to March...

We present updated parameters for the star HD 209458 and its transiting giant planet. The stellar angular diameter θ = 0.2254 ± 0.0017 mas is obtained from the...

We present new determinations of the positions of the planetary nebulae candidates found in Messier 33 by Magrini et al. (2000). The new coordinates have an...

Context. Wide-field spectrometers are needed to deal with current astrophysical challenges that require multiband observations at millimeter wavelengths. An...

Determining accurate plasma Doppler (line-of-sight) velocities from spectroscopic measurements is a challenging endeavour, especially when weak chromospheric...