gamma-Z corrections to forward-angle parity-violating e-p scattering
High Energy Physics - Phenomenology
2014-11-20 v3 High Energy Physics - Experiment
Nuclear Experiment
Nuclear Theory
Abstract
We use dispersion relations to evaluate the gamma-Z box contribution to parity-violating electron scattering in the forward limit arising from the axial-vector coupling at the electron vertex. The calculation makes full use of the critical constraints from recent JLab data on electroproduction in the resonance region as well as high energy data from HERA. At the kinematics of the Qweak experiment, this gives a correction of 0.0047{+0.0011}{-0.0004}$ to the Standard Model value 0.0713(8) of the proton weak charge. While the magnitude of the correction is highly significant, the uncertainty is within the anticipated experimental uncertainty of +- 0.003.
Cite
@article{arxiv.1002.0740,
title = {gamma-Z corrections to forward-angle parity-violating e-p scattering},
author = {A. Sibirtsev and P. G. Blunden and W. Melnitchouk and A. W. Thomas},
journal= {arXiv preprint arXiv:1002.0740},
year = {2014}
}
Comments
5 pages, 4 figures, expanded version to appear in Phys. Rev. D