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Stellar contributions to the diffuse soft X-ray backgroundOne of the results of the EINSTEIN/C.f.A. X-ray stellar survey was a determination of the contribution of the disk stellar population to the galactic component of the diffuse soft (0.28 - 1.0 keV) X-ray background. This analysis employed both binned and unbinned nonparametric statistical methods that have been developed by Avni, et al. (1980). These methods permitted the use of the information contained in both the 22 detections and 4 upper bounds on the luminosities of 26 dM stars in order to derive their luminosity function. Luminosity functions for earlier stellar types are not yet developed. For these earlier stellar types, the median luminosities as determined by Vaiana, et al., are used (1981), which underestimates their contribution to the background. We find that it is the M dwarfs that dominate the disk population stellar contribution to this background. To calculate the contribution of the stellar sources to the background, simple models both for the spatial distribution of the stars and for the properties of the intervening interstellar medium are used. A model is chosen in which all stellar classes have the same functional form for their spatial distribution: an exponentially decreasing distribution above the galactic equatorial plane, and a uniform distribution within the galactic plane for a region of several kiloparsecs centered on the Sun.
Document ID
Document Type
Conference Paper
Bookbinder, J. (Harvard-Smithsonian Center for Astrophysics Cambridge, MA, United States)
Avni, Y. (Weizmann Inst. Cambridge, MA, United States)
Golub, L. (Harvard-Smithsonian Center for Astrophysics Cambridge, MA, United States)
Rosner, R. (Einstein Observatory)
Vaiana, G. (Harvard-Smithsonian Center for Astrophysics)
Date Acquired
August 11, 2013
Publication Date
January 1, 1981
Publication Information
Publication: Smithsonian Astrophysics Observatory 2nd Cambridge Workshop on Cool Stars, Stellar Systems, and the Sun, Vol. 1
Subject Category
Distribution Limits
Work of the US Gov. Public Use Permitted.

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IDRelationTitle19830012575Analytic PrimarySecond Cambridge Workshop on Cool Stars, Stellar Systems, and the Sun, volume 1