Towards Fierz Interference Measurements in Neutron and $^{6}$He $\beta$ Decays*

Precision measurements in experiments with neutron and nuclear $\beta$ decays are sensitive to new physics beyond the Standard Model (SM). The signature of a possible exotic scalar or tensor contribution to the weak interaction would produce a small distortion to the $\beta$-decay energy spectrum relative to the SM prediction. To search for such a distortion, a high-precision measurement of the $\beta$-decay energy spectrum is required. Cyclotron Radiation Emission Spectroscopy (CRES) is a new elec- tron spectroscopy technique being developed by the Project 8 experiment, which is capable of measuring the energy of $\beta$ particles with high precision. This talk will explore the sensitivity potential of Fierz interference measurements in neutron and 6He decays using CRES. We will introduce the Fierz interference term and the CRES technique before presenting a survey of potential systematic uncertainties associated with CRES and their effects on the Fierz inteference term, a non-zero value of which would indicate the presence of scalar or tensor weak currents.\\ \\In collaboration with: Brent VanDevender, Pacific Northwest National Laboratory