New Insights of High-precision Asteroseismology: Acoustic Radius and χ²-matching Method for Solar-like Oscillator KIC 6225718

¹ Yunnan Observatories, Chinese Academy of Sciences, P.O. Box 110, Kunming 650216, China
² Key Laboratory for Structure and Evolution of Celestial Objects, Chinese Academy of Sciences, P.O. Box 110, Kunming 650216, China

^⋆ e-mail: wutao@ynao.ac.cn
^⋆⋆ e-mail: y@ynao.ac.cn

Published online: 27 October 2017

Abstract

Asteroseismology is a powerful tool for probing stellar interiors and determining stellar fundamental parameters. In the present work, we adopt the χ²-minimization method but only use the observed high-precision seismic observations (i.e., oscillation frequencies) to constrain theoretical models for analyzing solar-like oscillator KIC 6225718. Finally, we find the acoustic radius τ₀ is the only global parameter that can be accurately measured by the χ²-matching method between observed frequencies and theoretical model calculations for a pure p-mode oscillation star. We obtain seconds for KIC 6225718. It leads that the mass and radius of the CMMs are degenerate with each other. In addition, we find that the distribution range of acoustic radius is slightly enlarged by some extreme cases, which posses both a larger mass and a higher (or lower) metal abundance, at the lower acoustic radius end.