The MOLLER experiment

# The MOLLER experiment

The MOLLER experiment at Jefferson Lab will measure the weak charge of the electron, , $Q^e _W = 1 - 4 sin^2 \theta _W$ by measuring the PV asymmetry in electron-electron scattering. The measured asymmetry will be sensitive to faint but measurable deviations from precisely calculable predictions from SM. The MOLLER experiment will provide the best contact interaction search for leptons at low or high energy making it a probe of physics beyond the SM with sensitivities to mass scales of new PV physics up to 7.5 TeV. Such unprecedented sensitivity will results in a unique opportunity to new physics at the multi-TeV scale complementary to direct searches at high energy colliders. Possible new physics sensitivities include new $Z^0$ bosons and low mass dark-Z bosons. Best current limit on contact interaction scales available from LEP2 but LEP2 is only sensitive to parity conserving quantities ($g^2 _{RL}$ and $g^2 _{RR}+ g^2 _{LL}$) while MOLLER will be sensitive to parity violating new physics interactions.