We present a determination of the neutral current weak axial charge GAZ(0)=−0.654(3)stat(5)sys using the strange quark axial charge GAs(0) calculated with lattice QCD. We then perform a phenomenological analysis, where we combine the strange quark electromagnetic form factor from lattice QCD with (anti)neutrino-nucleon scattering differential cross section from MiniBooNE experiments in a momentum transfer region 0.24 ≲ Q2 ≲ 0.71 GeV2 to determine the neutral current weak axial form factor GAZ(Q2) in the range of 0 ≲ Q2 ≤ 1 GeV2. This yields a phenomenological value of GAZ(0) = −0.687(89)stat(40)sys. The value of GAZ(0) constrained by the lattice QCD calculation of GAs(0), when compared to its phenomenological determination, provides a significant improvement in precision and accuracy and can be used to provide a constraint on the fit to GAZ(Q2) for Q2> 0. This constrained fit leads to an unambiguous determination of (anti)neutrino-nucleon neutral current elastic scattering differential cross section near Q2 = 0 and can play an important role in numerically isolating nuclear effects in this region. We show a consistent description of GAZ(Q2) obtained from the (anti)neutrino-nucleon scattering cross section data requires a nonzero contribution of the strange quark electromagnetic form factor. We demonstrate the robustness of our analysis by providing a post-diction of the BNL E734 experimental data.
|Journal||Journal of High Energy Physics|
|State||Published - Jan 1 2020|
Bibliographical notePublisher Copyright:
© 2020, The Author(s).
- Lattice QCD
- Neutrino Physics
ASJC Scopus subject areas
- Nuclear and High Energy Physics