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

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