Extraction of the Axial Nucleon Form Factor from Neutrino Experiments on Deuterium

Understand

We present new parameterizations of vector and axial nucleon form factors.

• We maintain an excellent descriptions of the form factors at low momentum transfers ($Q^2$), where the spatial structure of the nucleon is important, and use the Nachtman scaling variable $\xi$ to relate elastic and inelastic form factors and impose quark-hadron duality constraints at high $Q^2$ where the quark structure dominates.
• We use the new vector form factors to re-extract updated values of the axial form factor from $\numu$ experiments on deuterium.
• We obtain an updated world average value from $\numu$d, $\numubar$H and pion electroproduction experiments of $M_{A}$ = $1.014 \pm 0.014 GeV/c^2$.