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Activity in X-ray-selected late-type starsA spectroscopic study has been conducted of nine X-ray bright late-type stars selected from two Einstein X-ray surveys: the Columbia Astrophysical Laboratory Survey (five stars) and the CFA Medium Sensitivity Survey (MSS; four stars). Spectral classes were determined and radial and V sin(i) velocities were measured for the stars. Four of the Columbia Survey stars were found to be new RS CVn-type binaries. The fifth Columbia survey star was found to be an active G dwarf star without evidence for binarity. None of the four MSS stars were found to be either binaries or optically active stars. Activity in these stars was assessed by measuring the excess emission in H-alpha and the Ca II IRT (8498, 8542) lines in comparison with inactive stars of similar spectral types. A correlation was found between X-ray luminosity and V sin(i) and H-alpha line excess. The measured excess line emission in H-alpha was also correlated with V sin(i) but not with the IRT line excess.
Document ID
Acquisition Source
Legacy CDMS
Document Type
Reprint (Version printed in journal)
External Source(s)
Takalo, Leo O.
(Pennsylvania State Univ. University Park, PA, United States)
Nousek, J. A.
(Pennsylvania State University University Park, United States)
Date Acquired
August 13, 2013
Publication Date
March 15, 1988
Publication Information
Publication: Astrophysical Journal, Part 1
Volume: 326
ISSN: 0004-637X
Subject Category
Accession Number
Funding Number(s)
Distribution Limits

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