Empirical determination of the lithium 6707.856 Å wavelength in young stars
Absorption features in stellar atmospheres are often used to calibrate photocentric velocities for the kinematic analysis of further spectral lines. The Li feature at ∼6708 Å is commonly used, especially in the case of young stellar objects, for which it is one of the strongest absorption lines. However, this complex line comprises two isotope fine-structure doublets. We empirically measured the wavelength of this Li feature in a sample of young stars from the PENELLOPE/VLT programme (using X-shooter, UVES, and ESPRESSO data) as well as HARPS data. For 51 targets, we fit 314 individual spectra using the STAR-MELT package, resulting in … Read more »