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Register a new userDynamical analysis and constraints for the HD 196885 system
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Added by
Cristian Andr\\'es Giuppone
Publication date
2012
fields
Physics
and research's language is
English
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The HD,196885 system is composed of a binary star and a planet orbiting the primary. The orbit of the binary is fully constrained by astrometry, but for the planet the inclination with respect to the plane of the sky and the longitude of the node are unknown. Here we perform a full analysis of the HD,196885 system by exploring the two free parameters of the planet and choosing different sets of angular variables. We find that the most likely configurations for the planet is either nearly coplanar orbits (prograde and retrograde), or highly inclined orbits near the Lidov-Kozai equilibrium points, i = 44^{circ} or i = 137^{circ} . Among coplanar orbits, the retrograde ones appear to be less chaotic, while for the orbits near the Lidov-Kozai equilibria, those around omega= 270^{circ} are more reliable, where omega_k is the argument of pericenter of the planets orbit with respect to the binarys orbit. From the observers point of view (plane of the sky) stable areas are restricted to (I1, Omega_1) sim (65^{circ}, 80^{circ}), (65^{circ},260^{circ}), (115^{circ},80^{circ}), and (115^{circ},260^{circ}), where I1 is the inclination of the planet and Omega_1 is the longitude of ascending node.
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