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arXiv · 2004.00022

Absolute dimensions of the unevolved F-type eclipsing binary BT Vulpeculae

Guillermo Torres·Claud H. Sandberg Lacy·Francis C. Fekel·Matthew W. Muterspaugh
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Abstract

We report extensive differential V-band photometry and high-resolution spectroscopy for the 1.14 day, detached, double-lined eclipsing binary BT Vul (F0+F7). Our radial-velocity monitoring and light curve analysis lead to absolute masses and radii of M1 = 1.5439 +/- 0.0098 MSun and R1 = 1.536 +/- 0.018 RSun for the primary, and M2 = 1.2196 +/- 0.0080 MSun and R2 = 1.151 +/- 0.029 RSun for the secondary. The effective temperatures are 7270 +/- 150 K and 6260 +/- 180 K, respectively. Both stars are rapid rotators, and the orbit is circular. A comparison with stellar evolution models from the MIST series shows excellent agreement with these determinations, for a composition of [Fe/H] = +0.08 and an age of 350 Myr. The two components of BT Vul are very near the zero-age main sequence.

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Guillermo Torres, Claud H. Sandberg Lacy, Francis C. Fekel, Matthew W. Muterspaugh. 2020-03-31. Absolute dimensions of the unevolved F-type eclipsing binary BT Vulpeculae. https://doi.org/10.3847/1538-4357%2Fab85c6

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