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Chromospherically active stars. III - HD 26337 = EI Eri: An RS CVn candidate for the Doppler-imaging techniqueSpectroscopic observations of the chromospherically active G5 IV single-lined binary HD 26337 = EI Eri are presented. An orbital period of 1.94722 days is found for the star. It has moderately strong Ca II H and K emission and strong ultraviolet emission features, while H-alpha is a weak absorption feature that is variable in strength. The inclination of the system is 46 + or - 12 deg, and the unseen secondary is probably a late K or early M dwarf. The v sin i of the primary is 50 + or - 3 km/s, resulting in a minimum radius of 1.9 + or - 0.1 solar radius. The star is within the required limits for Doppler imaging. The primary is close to filling its Roche lobe, resulting in a strong constraint that the mass ratio is 2.6 or greater, with a primary mass of at least 1.4 solar mass. The distance to the system is estimated at 75 pc.
Document ID
Document Type
Reprint (Version printed in journal)
External Source(s)
Fekel, Francis C. (Dyer Observatory, Nashville, TN; McDonald Observatory, Austin TX, United States)
Quigley, Robert (Western Washington University Bellingham, WA, United States)
Gillies, Kim (Dyer Observatory Nashville, TN, United States)
Africano, John L. (Kitt Peak National Observatory Tucson, AZ, United States)
Date Acquired
August 13, 2013
Publication Date
September 1, 1987
Publication Information
Publication: Astronomical Journal
Volume: 94
ISSN: 0004-6256
Subject Category
Funding Number(s)
Distribution Limits