Hostile tidal forces may inhibit the formation of Jovian planets in binaries with semimajor axes of 50?AU, binaries that might be called "close" in this context. As an alternative to in situ planet formation, a binary can acquire a giant planet when one of its original members is replaced in a dynamical interaction with another star that hosts a planet. Simple scaling relations for the structure and evolution of star clusters, coupled with analytic arguments regarding binary-single and binary-binary scattering, indicate that dynamical processes can deposit Jovian planets in 1% of close binaries. If ongoing and future exoplanet surveys measure a much larger fraction, it may be that giant planets do somehow form frequently in such systems.
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