Determination of the strange form factors of the nucleon from $\nu p$, $\bar{\nu }p$, and parity-violating $\vec{e}p$ elastic scattering

Abstract

A new method of obtaining the strange form factors of the nucleon is presented, in which forward-angle parity-violating $\vec{e}p$ elastic scattering data is combined with $\nu p$ and $\bar{\nu }p$ elastic scattering data. The axial form factor in electron-nucleon scattering is complicated by the presence of electro-weak radiative corrections that in principle need to be calculated or separately measured, but this axial form factor is suppressed at forward angles. The neutrino data has no such complication. Hence the use of forward-angle parity-violating $\vec{e}p$ data with $\nu p$ and $\bar{\nu }p$ data allows the extraction of all three strange form factors: electric, magnetic and axial ($G_E^s$, $G_M^s$, and $G_A^s$). In this letter, $\nu p$ and $\bar{\nu }p$ data from the Brookhaven E734 experiment are combined with the Jefferson Lab HAPPEX $\vec{e}p$ data to obtain two distinct solutions for the strange form factors at $Q^2$ = 0.5 GeV${}^2$. More generally, combining the neutrino elastic scattering data from E734 with the existing and upcoming $\vec{e}p$ data will yield the strange form factors of the nucleon for $Q^2$ of 0.45-1.05 GeV${}^2$. Measurement of $G_A^s$ is crucial to the determination of the strange quark contribution to the nucleon spin, $\Delta s$.

4 pages, 3 figures, 2 tables; to be submitted to Physical Review Letters

Cited by in corpus (13)

• The SAMPLE Experiment and Weak Nucleon Structure
• Flavor Structure of the Nucleon Sea
• Neutral current neutrino-nucleus interactions at intermediate energies
• Neutrino-nucleus quasi-elastic scattering and strange quark effects
• Strange Quark Contribution to the Vector and Axial Form Factors of the Nucleon: Combined Analysis of G0, HAPPEx, and Brookhaven E734 Data
• Ambiguities of neutrino(antineutrino) scattering on the nucleon due to the uncertainties of relevant strangeness form factors
• Strangeness content of the nucleon in quasielastic neutrino-nucleus reactions
• Strange nucleon form factors: Solitonic approach to $G_M^s$, $G_E^s$, ${\tilde{G}}_A^p$ and ${\tilde{G}}_A^n$ and comparison with world data
• Global Fit of Electron and Neutrino Elastic Scattering Data to Determine the Strange Quark Contribution to the Vector and Axial Form Factors of the Nucleon
• Flavor content of nucleon form factors in a VMD approach
• Electromagnetic and Axial-Vector Form Factors of the Quarks and Nucleon
• Flavor content of nucleon form factors in the space- and time-like region
• Quark flavor decomposition of the nucleon axial form factors