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Centro de Astrofísica da Universidade do Porto

The complementary roles of interferometry and asteroseismology in determining the mass of solar-type stars

O. L. Creevey, M. J. P. F. G. Monteiro, T. S. Metcalfe, T. M. Brown, S. J. Jimenez-Reyes, J. A. Belmonte

Abstract
How important is an independent diametermeasurement for the determination of stellar parameters of solar-type stars? When coupled with seismic observables, how well can we determine the stellar mass? If we can determine the radius of the star to between 1% and 4%, how does this affect the theoretical uncertainties? Interferometry can provide an independent radius determination and it has been suggested that we should expect at least a 4% precision on such a measurement for nearby solar-type stars. This study aims to provide both qualitative and
quantitive answers to these questions for a star such as our Sun, where seismic information will be available.
We show that the importance of an independent radius measurement depends on the combination of observables available and the size of the measurement errors. It is important for determining all stellar parameters and in particular the mass, where a good radius measurement can even allow us to determine the mass with a precision
better than 2%. Our results also show that measuring the small frequency separation δν significantly improves the determination of the evolutionary stage τ and the mixing-length parameter α.

Keywords
stars: oscillations— stars: fundamental parameters (mass, age, initial hydrogen abundance,mixing-length parameter)— stars: interiors— methods: numerical

The Astrophysical Journal
Volume 659, Page 616
April 2007

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