Detector for measuring the ${\pi }^{+}\to e^{+}{\nu }_e$ branching fraction

A. A. Aguilar-Arevalo, M. Aoki, M. Blecher +24

The PIENU experiment at TRIUMF is aimed at a measurement of the branching ratio $R^{e/\mu }$ = ${Γ\big((π^{+} \rightarrow e^{+} ν_{e}) + (π^{+} \rightarrow e^{+} ν_{e}γ)\big)}/{Γ\big(…