High-Dispersion Optical Spectra of Nearby Stars Younger Than The Sun

TL;DR

This study provides high-resolution optical spectra of 390 nearby stars younger than the Sun, analyzing their properties and revealing new insights into stellar activity and rotation correlations.

Contribution

It offers detailed stellar parameters for a large sample, including a novel finding on Ca II emission saturation at high rotational velocities.

Findings

Ca II chromospheric emission saturates at vsini > 30 km/s

Identified several spectroscopic binaries

Established correlations between age, rotation, and activity indices

Abstract

We present high-dispersion (R~16,000) optical (3900-8700 A) spectra of 390 stars obtained with the Palomar 60 inch telescope. The majority of stars observed are part of the Spitzer Legacy Science Program "The Formation and Evolution of Planetary Systems." Through detailed analysis we determine stellar properties for this sample, including radial and rotational velocities, Li I 6708 and Ha equivalent widths, the chromospheric activity index R'_HK, and temperature- and gravity-sensitive line ratios. Several spectroscopic binaries are also identified. From our tabulations, we illustrate basic age- and rotation-related correlations among measured indices. One novel result is that Ca II chromospheric emission appears to saturate at vsini values above ~30 km/s, similar to the well established saturation of X-rays that originate in the spatially separate coronal regions.