Quantum Anti-Zeno Effect in Nuclear \beta Decay

The acceleration of decay induced by frequency measurements, namely the quantum anti-Zeno effect (AZE), was first predicted by Kofman and Kurizki Nature 405 (2000) 546 . The effect of the frequency measurements on nuclear \beta decay rate is analyzed based on the time-dependent perturbation theory. We present a detailed calculation of the decay rates of ^3H, ^60Co (\beta^- type), ^22Na, ^106Ag (\beta^+ type) and ^18F, ^57Co and ^111Sn (EC type) under frequency measurements. It is found that the effects of frequency measurements on the decay rates of \beta^+ and \beta^- cases are different from the case of EC, and the smaller the \beta decay energy is, the more favorable it is to observe the AZE in experiment. Based on our analysis, it is suggested that possible experimental candidates should have a small decay energy and a reasonable half life (such as ^3H) for observing the AZE in \beta decay.