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The Einstein soft X-ray survey of the PleiadesThe results of a 0.1-4.5-keV X-ray survey of a 2 x 2-deg area centered on the Pleiades open cluster, performed using the imaging proportional counter and high-resolution imager of the Einstein Observatory on four days in 1980-1981, are presented in extensive tables, graphs, maps, histograms, and finding charts and characterized. A total of 61 sources are detected, and 44 of these are identified with cluster members of spectral types B-M. Findings discussed include Lx/Lbol of 10 the -7th for early-type stars; F-star mean Lx like that of F stars in the Hyades and in the field (denying time evolution of Lx); mean G-star Lx = 3.7 x 10 to the 29th erg/sec; G-star activity decay more gradual than 1/sq rt t, with sharp fall for t greater than 1 Gyr; and no evidence for X-ray-emissivity/rotational-velocity correlation in a homogeneous sample of K dwarfs or a sample of K and M stars with established V sin i data.
Document ID
19850043981
Document Type
Reprint (Version printed in journal)
External Source(s)
Authors
Caillault, J.-P. (Columbia Univ. New York, NY, United States)
Helfand, D. J. (Columbia University New York, NY, United States)
Date Acquired
August 12, 2013
Publication Date
February 1, 1985
Publication Information
Publication: Astrophysical Journal, Part 1
Volume: 289
ISSN: 0004-637X
Subject Category
ASTROPHYSICS
Funding Number(s)
CONTRACT_GRANT: NAS8-30753
CONTRACT_GRANT: AF-AFOSR-82-0014
Distribution Limits
Public
Copyright
Other