Weak decays of H-like ¹⁴⁰Pr⁵⁸⁺ and He-like ¹⁴⁰Pr⁵⁷⁺ ions

Abstract

The nuclear K-shell electron-capture (EC) and positron (β+) decay constants, λEC and λβ+ of H-like 140Pr58+ and He-like 140Pr57+ ions, measured recently in the experimental storage ring (ESR) at GSI, were calculated using standard weak interaction theory. The calculated ratios R=λEC/λβ+ of the decay constants agree with the experimental values within an accuracy better than 3%.