The MO/LLER experiment at Jefferson Lab: search for physics beyond the Standard Model

The MO/LLER experiment at Jefferson Lab will measure the parity‐violating analyzing power Az in the scattering of 11 GeV longitudinally polarized electrons from the atomic electrons in a liquid hydrogen target (Mo/ller scattering). In the Standard Model a non‐zero Az is due to the interference of the electromagnetic amplitude and the weak neutral current amplitude, the latter mediated by the Z0 boson. Az is predicted to be 35.6 parts per billion (ppb) at the kinematics of the experiment. It is the objective of the experiment to measure Az to a precision of 0.73 ppb. This result would yield a measurement of the weak charge of the electron QWe to a fractional error of 2.3% at an average value Q2 of 0.0056 (GeV/c)2. This in turn will yield a determination of the weak mixing angle sin2θw with an uncertainty of ±0.00026(stat) ±0.00013(syst), comparable to the accuracy of the two best determinations at high energy colliders (at the Z0 pole). Consequently, the result could potentially influence the central value...