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arXiv · 1609.02379

Spectroscopic and Interferometric Measurements of Nine K Giant Stars

Ellyn K. Baines·Michaela P. Döllinger·Eike W. Guenther·Artie P. Hatzes·Marie Hrudkovu·Gerard T. van Belle
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Abstract

We present spectroscopic and interferometric measurements for a sample of nine K giant stars. These targets are of particular interest because they are slated for stellar oscillation observations. Our improved parameters will directly translate into reduced errors in the final masses for these stars when interferometric radii and asteroseismic densities are combined. Here we determine each star's limb-darkened angular diameter, physical radius, luminosity, bolometric flux, effective temperature, surface gravity, metallicity, and mass. When we compare our interferometric and spectroscopic results, we find no systematic offsets in the diameters and the values generally agree within the errors. Our interferometric temperatures for seven of the nine stars are hotter than those determined from spectroscopy with an average difference of about 380 K.

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Ellyn K. Baines, Michaela P. Döllinger, Eike W. Guenther, Artie P. Hatzes, Marie Hrudkovu, Gerard T. van Belle. 2016-09-08. Spectroscopic and Interferometric Measurements of Nine K Giant Stars. https://doi.org/10.3847/0004-6256%2F152%2F3%2F66

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