Lattice Calculations of Nucleon Form Factors

Abstract

We present recent results of calculation of the isovector electromagnetic and axial form factors of the nucleon using lattice QCD with three different lattice actions and pion masses down to mπ≳300 MeV. Because of the precision of our high‐statistics calculations, we can test predictions of baryon chiral perturbation theory for the charge and axial radii of the nucleon. We find that currently available baryon ChPT calculations disagree with our data, indicating that the corresponding effective theory approximations are not valid above mπ≈300 MeV.