| Short-term dynamical interactions among extrasolar planets |
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| Author(s): Laughlin G, Chambers JE |
| Source: ASTROPHYSICAL JOURNAL Volume: 551 Issue: 1 Pages: L109-L113 Part: Part 2 Published: APR 18 2001 |
| Times Cited: 108 References: 6 |
| Abstract: We show that short-term perturbations among massive planets in multiple planet systems can result in radial velocity variations of the central star that differ substantially from velocity variations derived assuming the planets are executing independent Keplerian motions. We discuss two fitting methods that can lead to an improved dynamical description of multiple planet systems. In the first method, the osculating orbital elements are determined via a Levenberg-Marquardt minimization scheme driving an N-body integrator. The second method is an improved analytic model in which orbital elements are allowed to vary according to a simple model for resonant interactions between the planets. Both of these methods can determine the true masses for the planets by eliminating the degeneracy inherent in fits that assume independent Keplerian motions. We apply our fitting methods to the sin i GJ 876 radial velocity data and argue that the mass factors for the two planets are likely in the 1.25-2.0 range. |
| Document Type: Article |
| Language: English |
| Reprint Address: Laughlin, G (reprint author), NASA, Ames Res Ctr, Moffett Field, CA 94035 USA |
Addresses:
1. NASA, Ames Res Ctr, Moffett Field, CA 94035 USA
2. Armagh Observ, Armagh BT61 9DG, North Ireland |
| Publisher: UNIV CHICAGO PRESS, 1427 E 60TH ST, CHICAGO, IL 60637-2954 USA |
| Subject Category: Astronomy & Astrophysics |
| IDS Number: 423AR |
| ISSN: 0004-637X |