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arXiv · 1407.2574

Gold-plated moments of nucleon structure functions in baryon chiral perturbation theory

Vadim Lensky·Jose Manuel Alarcón·Vladimir Pascalutsa
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Abstract

We obtain leading- and next-to-leading order predictions of chiral perturbation theory for several prominent moments of nucleon structure functions. These free-parameter free results turn out to be in overall agreement with the available empirical information on nearly all of the considered moments, in the region of low-momentum transfer ($Q^2 < 0.3$ GeV$^2$). Especially surprising is the situation for the spin polarizability $δ_{LT}$, which thus far was not reproducible in chiral perturbation theory for proton and neutron simultaneously. This problem, known as the "$δ_{LT}$ puzzle," is not seen in the present calculation.

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Vadim Lensky, Jose Manuel Alarcón, Vladimir Pascalutsa. 2014-11-09. Gold-plated moments of nucleon structure functions in baryon chiral perturbation theory. https://doi.org/10.1103/physrevc.90.055202

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