Speaker
Mr
Tristan Sullivan
(University of British Columbia)
Description
The $\pi\rightarrow e \nu$ branching ratio
$R_\pi= \frac{ \Gamma(\pi\rightarrow e \nu + \pi\rightarrow
e \nu \gamma)}{\Gamma(\pi\rightarrow \mu \nu + \pi\rightarrow \mu \nu \gamma)},$
one of the most precisely calculated weak interaction Standard Model observables involving quarks,
provides a sensitive test of lepton universality and severe constraints on many new physics scenarios
with mass reach up to 1000 TeV. The PIENU experiment at TRIUMF aims to measure $R_\pi$ to a precision of less than 0.1%.
Results will be presented from an analysis of a subset of the data with statistical and
systematic uncertainties reduced to the 0.2% level, significantly improving on previous experiments.
Prospects for analyzing the full data set and further reducing the systematic error will also be discussed.
Primary author
Douglas Andrew Bryman
(University of British Columbia (CA))
Co-author
PIENU Collaboration
(ASU,BNL,Glasgow,KEK,Osaka,TRIUMF,Tsinghua,UBC,UNBC,UNAM,VPI)