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arXiv · 2207.03440

The isovector axial form factor of the nucleon from lattice QCD

Dalibor Djukanovic·Georg von Hippel·Jonna Koponen·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 perform a lattice-QCD based calculation of this form factor, introducing a new method to directly extract its $z$-expansion from lattice correlators. Our final parametrization of the form factor, which extends up to spacelike virtualities of $0.7\,{\rm GeV}^2$ with fully quantified uncertainties, agrees with previous lattice calculations but is significantly less steep than neutrino-deuterium scattering data suggests.

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Dalibor Djukanovic, Georg von Hippel, Jonna Koponen, Harvey B. Meyer, Konstantin Ottnad, Tobias Schulz, Hartmut Wittig. 2022-07-07. The isovector axial form factor of the nucleon from lattice QCD. https://arxiv.org/abs/2207.03440

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