New Measurement of the Rate for Pion Beta Decay

Abstract

The conserved-vector-current hypothesis, together with measured nuclear-beta-decay rates, predicts a value of the rate for the decay ${\pi }^{+}\to {\pi }^0{e}^{+}\nu$ of 0.4027±0.0018 ${\mathrm{s}}^{-1\mathrm{}}$. With use of a decay-in-flight technique the authors have made the most precise measurement to date of this rate, obtaining the value 0.398±0.015 ${\mathrm{s}}^{-1\mathrm{}}$, in good agreement with the prediction.