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arXiv · 1710.07544

Binary orbits from combined astrometric and spectroscopic data

L. B. Lucy
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Abstract

An efficient Bayesian technique for estimation problems in fundamental stellar astronomy is tested on simulated data for a binary observed both astrometrically and spectroscopically. Posterior distributions are computed for the components' masses and for the binary's parallax. One thousand independent repetitions of the simulation demonstrate that the 1- and 2-$\!\sigma$ credibility intervals for these fundamental quantities have close to the correct coverage fractions. In addition, the simulations allow the investigation of the statistical properties of a Bayesian goodness-of-fit criterion and of the corresponding p-value. The criterion has closely similar properties to the traditional chi^{2} test for minimum-chi^{2} solutions.

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L. B. Lucy. 2017-10-20. Binary orbits from combined astrometric and spectroscopic data. https://doi.org/10.1051/0004-6361%2F201732145

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