On the Dynamical Stability of Gamma Cephei, an S-Type Binary Planetary System

Nader Haghighipour

doi:10.1063/1.1774536

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arXiv · astro-ph/0403312

On the Dynamical Stability of Gamma Cephei, an S-Type Binary Planetary System

Nader Haghighipour

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Abstract

Precision radial velocity measurements of the Gamma Cephei (HR8974) binary system suggest the existence of a planetary companion with a minimum mass of 1.7 Jupiter-mass on an elliptical orbit with a ~2.14 AU semimajor axis and 0.12 eccentricity (hatzes et al. 2003). I present in this paper a summary of the results of an extensive numerical study of the orbital stability of this three-body system for different values of the semimajor axis and orbital eccentricity of the binary, and also the orbital inclination of the planet. Numerical integrations indicate that the system is stable for the planet's orbital inclination ranging from 0 to 60 degrees, and for the binary's orbital eccentricity less than 0.5. The results also indicate that for large values of the inclination, the system may be locked in a Kozai resonance.

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Nader Haghighipour. 2004-03-12. On the Dynamical Stability of Gamma Cephei, an S-Type Binary Planetary System. https://doi.org/10.1063/1.1774536

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