Accessing weak neutral-current coupling $g_{AA}^{eq}$ using positron and electron beams at Jefferson Lab

Abstract

Low-energy neutral-current couplings arising in the Standard Model of electroweak interactions can be constrained in lepton scattering off hydrogen or a nuclear fixed target. Recent polarized electron scattering experiments at Jefferson Lab (JLab) have improved the precision in the parity-violating types of effective couplings. On the other hand, the only known way to access the parity-conserving counterparts is to compare scattering cross sections between a lepton and an anti-lepton beam. We review the current knowledge of both types of couplings and how to constrain them. We also present exploratory calculations for a possible measurement of $g_{AA}^{eq}$ using the planned SoLID spectrometer combined with a possible positron beam at JLab.

8 pages, 6 figures, manuscript accepted by EPJA

References in corpus (3)

• Parton distributions in the LHC era: MMHT 2014 PDFs
• Precision Measurement of the Weak Charge of the Proton
• Measurement of Parity-Violating Asymmetry in Electron-Deuteron Inelastic Scattering

Cited by in corpus (5)

• An experimental program with high duty-cycle polarized and unpolarized positron beams at Jefferson Lab
• Neutral-Current Electroweak Physics and SMEFT Studies at the EIC
• Sensitivity of Parity-violating Electron Scattering to a Dark Photon
• Reflections on Chiral Symmetry within QCD
• Challenges in the extraction of physics beyond the Standard Model from electron scattering