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A dynamical mechanism for establishing apsidal resonance

Renu Malhotra
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Abstract

We show that in a system of two planets initially in nearly circular orbits, an impulse perturbation that imparts a finite eccentricity to one planet's orbit causes the other planet's orbit to become eccentric as well, and also naturally results in a libration of their relative apsidal longitudes for a wide range of initial conditions. We suggest that such a mechanism may explain orbital eccentricities and apsidal resonance in some exo-planetary systems. The eccentricity impulse could be caused by the ejection of a planet from these systems, or by torques from a primordial gas disk. The amplitude of secular variations provides an observational constraint on the dynamical history of such systems.

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Renu Malhotra. 2002-07-04. A dynamical mechanism for establishing apsidal resonance. https://doi.org/10.1086/342637

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