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arXiv · 1702.01513

Electromagnetic form factors at large momenta from lattice QCD

A. J. Chambers·J. Dragos·R. Horsley·Y. Nakamura·H. Perlt·D. Pleiter·P. E. L. Rakow·G. Schierholz·A. Schiller·K. Somfleth·H. Stüben·R. D. Young·J. Zanotti
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Abstract

Accessing hadronic form factors at large momentum transfers has traditionally presented a challenge for lattice QCD simulations. Here we demonstrate how a novel implementation of the Feynman-Hellmann method can be employed to calculate hadronic form factors in lattice QCD at momenta much higher than previously accessible. Our simulations are performed on a single set of gauge configurations with three flavours of degenerate mass quarks corresponding to $m_\pi \approx 470 \text{ MeV}$. We are able to determine the electromagnetic form factors of the pion and nucleon up to approximately $6 \text{ GeV}^2$, with results for $G_E/G_M$ in the proton agreeing well with experimental results.

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A. J. Chambers, J. Dragos, R. Horsley, Y. Nakamura, H. Perlt, D. Pleiter, P. E. L. Rakow, G. Schierholz, A. Schiller, K. Somfleth, H. Stüben, R. D. Young, J. Zanotti. 2017-02-06. Electromagnetic form factors at large momenta from lattice QCD. https://doi.org/10.1103/physrevd.96.114509

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