Parallax and Distance Estimates for Fourteen Cataclysmic Variable Stars

J. R. Thorstensen

doi:10.1086/379308

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arXiv · astro-ph/0308516

Parallax and Distance Estimates for Fourteen Cataclysmic Variable Stars

J. R. Thorstensen

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Abstract

I used the 2.4 m Hiltner telescope at MDM Observatory in an attempt to measure trigonometric parallaxes for 14 cataclysmic variable stars. Techniques are described in detail. In the best cases the parallax uncertainties are below 1 mas, and significant parallaxes are found for most of the program stars. A Bayesian method which combines the parallaxes together with proper motions and absolute magnitude constraints is developed and used to derive distance estimates and confidence intervals. The most precise distance derived here is for WZ Sge, for which I find 43.3 (+1.6, -1.5) pc. Six Luyten Half-Second stars with previous precise parallax measurements were re-measured to test the techniques, and good agreement is found.

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J. R. Thorstensen. 2003-08-28. Parallax and Distance Estimates for Fourteen Cataclysmic Variable Stars. https://doi.org/10.1086/379308

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