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Improved Light-Cone Sum Rules for the Electromagnetic Form Factors of the Nucleon

Alexander Lenz·Markus Wittmann·Eckart Stein
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Abstract

We calculate the electromagnetic form factors of the nucleon within the light-cone sum rule approach. In comparison to previous work (hep-ph/0112085) we suggest to use a pure isospin-1/2 interpolating field for the nucleon, since the Chernyak-Zhitnitsky current leads to numerically large, unphysical, isospin violating contributions. The leading-order sum rules are derived for the form factors and the results are confronted with the experimental data. Our approach tends to favor the nucleon distribution amplitudes that are not far from the asymptotic shape.

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Alexander Lenz, Markus Wittmann, Eckart Stein. 2003-11-06. Improved Light-Cone Sum Rules for the Electromagnetic Form Factors of the Nucleon. https://doi.org/10.1016/j.physletb.2003.12.009

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