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Centro de Astrofísica da Universidade do Porto

Verifying asteroseismically determined parameters of Kepler stars using Hipparcos parallaxes: self-consistent stellar properties and distances

V. Silva Aguirre, L. Casagrande, S. Basu, T. L. Campante, W. J. Chaplin, D. Huber, A. Miglio, A. M. Serenelli, J. Ballot, T. R. Bedding, J. Christensen-Dalsgaard, O. L. Creevey, Y. Elsworth, R. A. García, R. L. Gilliland, S. Hekker, H. Kjeldsen, S. Mathur, T. S. Metcalfe, M. J. P. F. G. Monteiro, B. Mosser, M. H. Pinsonneault, D. Stello, A. Weiss, P. Tenenbaum, J. D. Twicken, K. Uddin

Abstract
Accurately determining the properties of stars is of prime importance for characterizing stellar populations in our Galaxy. The field of asteroseismology has been thought to be particularly successful in such an endeavor for stars in different evolutionary stages. However, to fully exploit its potential, robust methods for estimating stellar parameters are required and independent verification of the results is mandatory. With this purpose, we present a new technique to obtain stellar properties by coupling asteroseismic analysis with the InfraRed Flux Method. By using two global seismic observables and multi-band photometry, the technique allows us to obtain masses, radii, effective temperatures, bolometric fluxes, and hence distances for field stars in a self-consistent manner. We apply our method to 22 solar-like oscillators in the Kepler short-cadence sample, that have accurate Hipparcos parallaxes. Our distance determinations agree to better than 5%, while measurements of spectroscopic effective temperatures and interferometric radii also validate our results. We briefly discuss the potential of our technique for stellar population analysis and models of Galactic Chemical Evolution.

Keywords
asteroseismology – parallaxes – stars: distances – stars: fundamental parameters – stars: oscillations

The Astrophysical Journal
Volume 757, Page 99_1
September 2012

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