The MECO experiment: A search for lepton flavor violation in muonic atoms

Abstract

MECO will search for direct evidence of muon and electron flavor violation in the decay of muons in Coulomb bound states via coherent recoil of the nucleus and decay electron. The expected sensitivity to the $\mu^{-} {\rm N} \to e^{-} + {\rm N}$ branching fraction relative to muon capture $\mu^{-} {\rm N}(A,Z) \to \nu_{\mu} + {\rm N}(A,Z-1)$ is $R_{\mu e} < 5\times 10^{-17}$ at 90% confidence level, roughly three to four orders of magnitude lower than current limits. This article provides an overview of the experiment.