On the Inference of a Star's Inclination Angle from its Rotation Velocity and Projected Rotation Velocity

Abstract

It is possible to learn about the orientation of a star's rotation axis by combining measurements of the star's rotation velocity ($v$) and its projection onto our line of sight ($v\sin i$). This idea has found many applications, including the investigation of the obliquities of stars with transiting planets. Here, we present a method for the probabilistic inference of the inclination of the star's rotation axis based on independent data sets that constrain $v$ and $v\sin i$. We also correct several errors and misconceptions that appear in the literature.

accepted for publication in AJ [7 pages]

References in corpus (4)

• Obliquities of Kepler Stars: Comparison of Single- and Multiple-Transit Systems
• The Rotation Period of the Planet-Hosting Star HD 189733
• Spin alignment of stars in old open clusters
• Bayesian hierarchical inference of asteroseismic inclination angles

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