TWIST Measurement of the Decay Parameters rho and delta of Normal Muon Decay

The TWIST collaboration is improving the precision on the characterization of normal muon decay, $\mu^+\rightarrow e^+\nu_e\bar{\nu}_{\mu}$, through measurements of the decay parameters $\rho$, $\delta$ and $P_{\mu}\xi$. The analysis of the initial TWIST measurements of $\rho$ and $\delta$ have been completed. We find $\rho=0.75080\pm0.00032(stat.)\pm0.00097(syst.)\pm0.00023 $ and $\delta=0.74964\pm0.00066(stat.)\pm0.00112(syst.)$, consistent with the Standard Model. The improved precision places new limits on physics beyond the Standard Model, such as the parameters describing left-right symmetric models. The current results and implications will be discussed.