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High-Resolution Spectroscopy of Some Very Active Southern Stars

David R. Soderblom·Jeremy R. King·Todd J. Henry
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Abstract

We have obtained high-resolution echelle spectra of 18 solar-type stars that an earlier survey showed to have very high levels of Ca II H and K emission. Most of these stars belong to close binary systems, but 5 remain as probable single stars or well-separated binaries that are younger than the Pleiades on the basis of their lithium abundances and H-alpha emission. Three of these probable single stars also lie more than 1 magnitude above the main sequence in a color-magnitude diagram, and appear to have ages of 10 to 15 Myr. Two of them, HD 202917 and HD 222259, also appear to have a kinematical association with the pre-main sequence multiple system HD 98800.

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David R. Soderblom, Jeremy R. King, Todd J. Henry. 1998-03-10. High-Resolution Spectroscopy of Some Very Active Southern Stars. https://doi.org/10.1086/300423

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