Precise branching ratio measurements in $^{19}$Ne beta decay and fundamental tests of the weak interaction

TL;DR

This study achieved high-precision measurements of $^{19}$Ne beta decay branching ratios, refining tests of weak interaction symmetries and contributing to fundamental physics understanding.

Contribution

It provides the most precise determination to date of the superallowed beta decay branch in $^{19}$Ne, enhancing the accuracy of weak interaction tests.

Findings

Superallowed $1/2^+ o 1/2^+$ beta branch in $^{19}$F is 99.9878(7)%

Measurement precision is three times higher than previous data

Implications for testing weak interaction symmetries are discussed

Abstract

We used the 8$\pi$ $\gamma$-ray spectrometer at the TRIUMF-ISAC radiocative ion beam facility to obtain high-precision branching ratios for $^{19}$Ne $\beta^+$ decay to excited states in $^{19}$F. Together with other previous work, our measurements determine the superallowed $1/2^+ \to 1/2^+$ beta branch to the ground state in $^{19}$F to be 99.9878(7)\%, which is three times more precise than known previously. The implications of these measurements for testing a variety of weak interaction symmetries are discussed briefly.