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arXiv · 0908.2137

Distance to U Pegasi by the DDE Algorithm

T. R. Vaccaro·Dirk Terrell·R. E. Wilson
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Abstract

A distance is found for the W UMa type binary U Pegasi, with a newly modified version of the Wilson-Devinney program (W-D) that makes use of the direct distance estimation (DDE) algorithm. The reported distance of d = 123.6pc is an average based on solutions for B and V data and a primary star temperature of 5800K. Standardized light curves (not differential), radial velocities, and a spectroscopic primary star temperature are input to the pro- gram. Differential corrections were performed for each light curve band along with the velocities for two primary temperatures that span 100K. Log10d is a model parameter like many others that are adjustable in W-D. The eclipsing binary distance agrees with the Hipparcos parallax distance and is more precise.

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T. R. Vaccaro, Dirk Terrell, R. E. Wilson. 2009-08-15. Distance to U Pegasi by the DDE Algorithm. https://arxiv.org/abs/0908.2137

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