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

R. J. White; J. M. Gabor; L. A. Hillenbrand

doi:10.1086/514336

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arXiv · 0706.0542

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

R. J. White·J. M. Gabor·L. A. Hillenbrand

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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.

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R. J. White, J. M. Gabor, L. A. Hillenbrand. 2007-06-04. High-Dispersion Optical Spectra of Nearby Stars Younger Than The Sun. https://doi.org/10.1086/514336

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