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Analysis of the Low-Energy Theorem for γp \to p π^0

H. W. L. Naus·R. M. Davidson
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Abstract

The derivation of the `classical' low-energy theorem (LET) for γp \rightarrow pπ^0 is re-examined and compared to chiral perturbation theory. Both results are correct and are not contradictory; they differ because different expansions of the same quantity are involved. Possible modifications of the extended partially conserved axial-vector current relation, one of the starting points in the derivation of the LET, are discussed. An alternate, more transparent form of the LET is presented.

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H. W. L. Naus, R. M. Davidson. 1995-06-28. Analysis of the Low-Energy Theorem for γp \to p π^0. https://doi.org/10.1007/s002180050053

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