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On Orbital Elements of Extrasolar Planetary Candidates and Spectroscopic BinariesWe estimate probability densities of orbital elements, periods, and eccentricities, for the population of extrasolar planetary candidates (EPC) and, separately, for the population of spectroscopic binaries (SB) with solar-type primaries. We construct empirical cumulative distribution functions (CDFs) in order to infer probability distribution functions (PDFs) for orbital periods and eccentricities. We also derive a joint probability density for period-eccentricity pairs in each population. Comparison of respective distributions reveals that in all cases EPC and SB populations are, in the context of orbital elements, indistinguishable from each other to a high degree of statistical significance. Probability densities of orbital periods in both populations have P(exp -1) functional form, whereas the PDFs of eccentricities can he best characterized as a Gaussian with a mean of about 0.35 and standard deviation of about 0.2 turning into a flat distribution at small values of eccentricity. These remarkable similarities between EPC and SB must be taken into account by theories aimed at explaining the origin of extrasolar planetary candidates, and constitute an important clue us to their ultimate nature.
Document ID
Document Type
Reprint (Version printed in journal)
Stepinski, T. F. (Lunar and Planetary Inst. Houston, TX United States)
Black, D. C. (Lunar and Planetary Inst. Houston, TX United States)
Date Acquired
August 20, 2013
Publication Date
January 1, 2001
Publication Information
Publication: Astronomy and Astrophysics
Volume: 371
ISSN: 0004-6361
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Report/Patent Number
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