Efficient fitting of multiplanet keplerian models to radial velocity and astrometry data

J. T. Wright, A. W. Howard

Research output: Contribution to journalArticle

136 Citations (Scopus)

Abstract

We describe a technique for solving for the orbital elements of multiple planets from radial velocity (RV) and/or astrometric data taken with 1ms -1 and μas precision, appropriate for efforts to detect Earth-massed planets in their stars' habitable zones, such as NASA's proposed Space Interferometry Mission. We include details of calculating analytic derivatives for use in the Levenberg-Marquardt (LM) algorithm for the problems of fitting RV and astrometric data separately and jointly. We also explicate the general method of separating the linear and nonlinear components of a model fit in the context of an LM fit, show how explicit derivatives can be calculated in such a model, and demonstrate the speed up and convergence improvements of such a scheme in the case of a five-planet fit to published RV data for 55 Cnc.

Original languageEnglish (US)
Pages (from-to)205-215
Number of pages11
JournalAstrophysical Journal, Supplement Series
Volume182
Issue number1
DOIs
StatePublished - Jul 27 2009

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astrometry
radial velocity
planet
planets
orbital elements
interferometry
stars

All Science Journal Classification (ASJC) codes

  • Astronomy and Astrophysics
  • Space and Planetary Science

Cite this

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Efficient fitting of multiplanet keplerian models to radial velocity and astrometry data. / Wright, J. T.; Howard, A. W.

In: Astrophysical Journal, Supplement Series, Vol. 182, No. 1, 27.07.2009, p. 205-215.

Research output: Contribution to journalArticle

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