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arXiv · 2212.01208

Isovector Axial Form Factor of the Nucleon from Lattice QCD

Jonna Koponen·Dalibor Djukanovic·Georg von Hippel·Harvey B. Meyer·Konstantin Ottnad·Tobias Schulz·Hartmut Wittig
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Abstract

The isovector axial form factor of the nucleon plays a key role in interpreting data from long-baseline neutrino oscillation experiments. We present a lattice QCD calculation of this form factor, introducing a new method to directly extract its z-expansion from lattice correlators. Our final parameterization of the form factor, which extends up to spacelike virtualities of 0.7 GeV^2 with fully quantified uncertainties, agrees with previous lattice calculations but is significantly less steep than neutrino-deuterium scattering data suggests.

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Jonna Koponen, Dalibor Djukanovic, Georg von Hippel, Harvey B. Meyer, Konstantin Ottnad, Tobias Schulz, Hartmut Wittig. 2022-12-02. Isovector Axial Form Factor of the Nucleon from Lattice QCD. https://arxiv.org/abs/2212.01208

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