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arXiv · hep-ph/9910256

Generalized Drell-Hearn-Gerasimov Sum Rule at Order {\cal O}(p^4) in Chiral Perturbation Theory

Xiangdong Ji·Chung-Wen Kao·Jonathan Osborne
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Abstract

We calculate the forward spin-dependent photon-nucleon Compton amplitudes $S_1$ and $S_2$ as functions of photon energy $ν$ and mass $Q^2$ at the next-to-leading (${\cal O}(p^4)$) order in chiral perturbation theory, from which we extract the contribution to a generalized Drell-Hearn-Gerasimov sum rule at low $Q^2$. The result indicates a much rapid $Q^2$ variation of the sum rule than a simple dimensional analysis would yield.

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Xiangdong Ji, Chung-Wen Kao, Jonathan Osborne. 1999-10-06. Generalized Drell-Hearn-Gerasimov Sum Rule at Order {\cal O}(p^4) in Chiral Perturbation Theory. https://doi.org/10.1016/s0370-2693(99)01365-9

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