Hi-Res Spectroscopy of a Volume-Limited Hipparcos Sample within 100 parsecs

Pey-Lian Lim

Accurate parallax measurements of solar neighborhood stars from the Hipparcos catalog have enabled concrete distance and luminosity determinations. Subgiants are of particular interest because they lie in an area where isochrones are well separated, allowing for precise age determination. Coupled with high-resolution spectroscopy, we can investigate abundance patterns, chemical evolution, and the age-metallicity relationship. We can incorporate observational contrains into star formation history technique.

We obtain high-resolution echelle spectra of evolved Hipparcos stars, subgiants in particular, in a volume-limited sample within 100 parsec. We have developed automatic analysis methods for the derivation of stellar properties and abundances. We also obtain stellar ages, masses, and kinematics. In this work, we present our results from the automatic analysis methods, compare the values with literature, and investigate age and abundance patterns. Finally, we discuss possible improvements and future development of this project.