Beryllium in the Sun: Re-Measurement and Implications

Abstract

The solar beryllium abundance is important because it provides a constraint on the depth to which mixing has occurred below the surface convective zone. Unlike helioseismology which only maps the present-day Sun, the solar beryllium abundance provides an integrated picture of mixing over the entire history of the Sun. In this review I outline the logic involving the ‘missing UV opacity’ that required that the solar beryllium abundance be re-determined. A brief summary of the empirical process of estimating the “missing UV opacity” is given along with a confirmation based on a recent re-calculation of the Fe I bound-free opacity. The addition of this opacity resulted in our finding that the solar beryllium abundance was meteoritic. The implications of this result in the context of mixing in solar-type stars is discussed.