Parity violating Moller scattering asymmetry up to the two-loop level

TL;DR

This paper calculates two-loop level contributions to parity-violating Moller scattering asymmetry, providing theoretical predictions crucial for upcoming high-precision experiments like MOLLER and ILC.

Contribution

It presents the first detailed two-loop calculations of electroweak corrections to Moller scattering asymmetry, including chiral amplitudes and QED correction cancellations.

Findings

QED corrections cancel at asymmetry level except vacuum-polarization.

Two-loop contributions are numerically comparable to experimental accuracy.

Results are relevant for upcoming precision measurements at Jefferson Laboratory and ILC.

Abstract

The paper investigates contributions of $Z$, $W$ and $\gamma$ intermediate states to the parity-violating Moller scattering asymmetry up to two-loop level. Using the Yennie--Frautschi--Suura factorization form for amplitudes, we demonstrate that QED corrections, with an exception of vacuum-polarization effects, cancel at the asymmetry level. We obtain chiral amplitudes at Born, one-loop and partially at two-loop level: boxes with lepton self-energies, ladder boxes and decorated boxes. Our calculations are relevant for the ultra-precise 11 GeV MOLLER experiment planned at Jefferson Laboratory and future ILC experiments. The numerical comparision of the two-loop contributions with the experimental accuracy of MOLLER is provided.