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Chromospherically active stars. 13: HD 30957: A double lined K dwarf binaryHD 30957 is a double-lined spectroscopic binary with a period of 44.395 days and a modest eccentricity of 0.09. The spectral types of the components are K2-3 V and K5 V. The measured v sin i for both components is less than or equal to 3 km/s and the orbital inclination is estimated to be 69 deg. The system is relatively nearby with a parallax of 0.025 sec or a distance of 40 pc. Space motions of the system indicate that it does not belong to any of the known moving groups. Absolute surface fluxes of the Ca II H and K lines have been recomputed and indicate only modest chromospheric activity. If the stars are rotating pseudosynchronously, the lack of light variability is consistent with the value of the critical Rossby number for starspot activity.
Document ID
Document Type
Reprint (Version printed in journal)
External Source(s)
Fekel, Francis C. (NASA Marshall Space Flight Center Huntsville, AL, United States)
Dadonas, Virgilijus (Vilnius University Vilnius, Lithuania)
Sperauskas, Julius (Vilnius University Vilnius, Lithuania)
Vaccaro, Todd R. (Vanderbilt University Nashville, TN, United States)
Patterson, L. Ronald (Vanderbilt University Nashville, TN, United States)
Date Acquired
August 16, 2013
Publication Date
November 1, 1994
Publication Information
Publication: The Astronomical Journal
Volume: 108
Issue: 5
ISSN: 0004-6256
Subject Category
Funding Number(s)
Distribution Limits