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arXiv · 1103.4892

Axial anomaly and the delta_{LT} puzzle

Nikolai Kochelev·Yongseok Oh
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Abstract

The axial anomaly contribution to generalized longitudinal-transverse polarizability $\delta_{LT}^{}$ is calculated within Regge approach. It is shown that the contribution from the exchange of the $a_1^{}(1260)$ Regge trajectory is nontrivial and might have the key role to explain the large difference between the predictions of chiral perturbation theory and the experimental data for the neutron $\delta_{LT}^{}$. We also present the prediction for the proton $\delta_{LT}^{}$, which will be measured at the Thomas Jefferson National Accelerator Facility in near future.

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Nikolai Kochelev, Yongseok Oh. 2011-03-25. Axial anomaly and the delta_{LT} puzzle. https://doi.org/10.1103/physrevd.85.016012

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