Dispersion γz-box correction to the weak charge of the proton

M. Gorchtein, C. J. Horowitz

Research output: Contribution to journalArticlepeer-review

70 Scopus citations

Abstract

We consider elastic scattering of electrons off a proton target. The parity-violating (PV) asymmetry arises at leading order in α due to interference of γ and Z exchange. The radiative corrections to this leading mechanism were calculated in the literature and included in experimental analyses, except for γZ-box and cross-box contributions. We present here a dispersion calculation of these corrections in forward kinematics. We demonstrate that at the GeV energies of current PV experiments, such corrections are not suppressed by the small vector weak charge of the electron, as occurs in the atomic parity violation. Our results suggest that the current theoretical uncertainty in the analysis of the QWEAK experiment might be substantially underestimated, and more accurate accounts of the dispersion corrections are needed in order to interpret the PV data.

Original languageEnglish
Article number091806
JournalPhysical Review Letters
Volume102
Issue number9
DOIs
StatePublished - 2 Mar 2009
Externally publishedYes

Fingerprint

Dive into the research topics of 'Dispersion γz-box correction to the weak charge of the proton'. Together they form a unique fingerprint.

Cite this