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The unprecedented quality of the asteroseismic data of solar-type stars madeavailable by space missions such as NASA's Kepler telescope are making itpossible to explore stellar interior structures. This offers possibilities ofconstraining stellar core properties (such as core sizes, abundances, andphysics) paving the way for improving the precision of the inferred stellarages. We employ 16 Cyg A and B as our benchmark stars for an asteroseismicstudy in which we present a novel approach aimed at selecting from a sample ofacceptable stellar models returned from Forward Modelling techniques, down tothe ones that better represent the core of each star. This is accomplished bycomparing specific properties of the observed frequency ratios for each star tothe ones derived from the acceptable stellar models. We demonstrate that inthis way we are able to constrain further the hydrogen mass fraction in thecore, establishing the stars' precise evolutionary states and ages. The rangesof the derived core hydrogen mass fractions are [0.01 - 0.06] and [0.12 - 0.19]for 16 Cyg A and B, respectively, and, considering that the stars are coeval,the age and metal mass fraction parameters span the region [6.4 - 7.4] Gyr and[0.023 - 0.026], respectively. In addition, our findings show that using asingle helium-to-heavy element enrichment ratio, ($\Delta Y/\Delta Z$), whenforward modelling the 16 Cyg binary system, may result in a sample ofacceptable models that do not simultaneously fit the observed frequency ratios,further highlighting that such an approach to the definition of the heliumcontent of the star may not be adequate in studies of individual stars.

On the stellar core physics of the 16 Cyg binary system: constraining the central hydrogen abundance using asteroseismology