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arXiv · hep-lat/0312023

Pion structure from improved lattice QCD: form factor and charge radius at low masses

J. van der Heide·J. Koch·E. Laermann
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Abstract

The charge form factor of the pion is calculated in lattice QCD. The non-perturbatively improved Sheikholeslami-Wohlert action is used together with the $\mathcal{O}(a)$ improved vector current. Other choices for the current are examined. The form factor is extracted for pion masses from 970 MeV down to 360 MeV and for momentum transfers $Q^2 \leq 2 \mathrm{GeV}^2$. The mean square charge radius is extracted, compared to previous determinations and its extrapolation to lower masses discussed.

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J. van der Heide, J. Koch, E. Laermann. 2004-03-16. Pion structure from improved lattice QCD: form factor and charge radius at low masses. https://doi.org/10.1103/physrevd.69.094511

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