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arXiv · 1310.3856

Absolute Properties of the Triple Star HP Aurigae

Claud H. Sandberg Lacy·Guillermo Torres·Marek Wolf·Charles L. Burks
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Abstract

New photometric, spectroscopic, and eclipse timing observations of the eclipsing binary star HP Aur allow for very accurate orbital determinations, even in the presence of a third body and transient starspot activity. The eclipsing binary masses are determined to an accuracy of +/-0.4% and the radii to +/-0.6%. The masses are 0.9543 +/- 0.0041 and 0.8094 +/- 0.0036 solar masses, and the radii are 1.0278 +/- 0.0042 and 0.7758 +/- 0.0034 solar radii, respectively. The orbital period in the outer orbit is accurately known for the first time - 4.332 +/- 0.011 years. A comparison with current theories of stellar evolution show that the components absolute properties can be well-matched by the current models at an age of about 7 billion years.

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Claud H. Sandberg Lacy, Guillermo Torres, Marek Wolf, Charles L. Burks. 2013-10-14. Absolute Properties of the Triple Star HP Aurigae. https://doi.org/10.1088/0004-6256%2F147%2F1%2F1

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