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Chromospheric CaII Emission in Nearby F, G, K, and M stars

Jason T. Wright·Geoffrey W. Marcy·R. Paul Butler·Steve S. Vogt
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Abstract

We present chromospheric CaII activity measurements, rotation periods and ages for ~1200 F-, G-, K-, and M- type main-sequence stars from ~18,000 archival spectra taken at Keck and Lick Observatories as a part of the California and Carnegie Planet Search Project. We have calibrated our chromospheric S values against the Mount Wilson chromospheric activity data. From these measurements we have calculated median activity levels and derived R'HK, stellar ages, and rotation periods for 1228 stars, ~1000 of which have no previously published S values. We also present precise time series of activity measurements for these stars.

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Jason T. Wright, Geoffrey W. Marcy, R. Paul Butler, Steve S. Vogt. 2004-02-24. Chromospheric CaII Emission in Nearby F, G, K, and M stars. https://doi.org/10.1086/386283

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