Setting limits on a new parameter outside of Standard Model muon decay.

This work is a response to predictions concerning a new tensor interaction which is outside of the Michel local interactions of Standard Model muon decay. This interaction is assumed to be parameterized by the addition of a new variable, $\kappa $, to the differential decay probability spectrum. The \textit{TWIST} experiment is measuring the Michel parameters $\rho $, $P_{\mu }\xi $, and $\delta $ in muon decay to search for deviations from the Standard Model. Our analysis was of the approximate contribution that $\kappa $ would make to the \textit{TWIST} measurements and the sensitivity of this contribution to the fitted momentum range. Efforts were made to set a limit on $\kappa $ in accordance with both past \textit{TWIST} fit ranges and assumed future ones.