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Comment on "Subleading Corrections to Parity Violating Pion Photoproduction"

Jiunn-Wei Chen·Xiangdong Ji
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Abstract

In a recent preprint, hep-ph/0012253, Zhu et al. calculated a part of the next-to-leading order corrections to parity-violating pion photoproduction (pol)gamma p-> pi^+ n in heavy-baryon chiral perturbation theory. They claim they have found the contribution as large as the leading-order. If correct, the process will not be a clean way to extract the longest range PV pion-nucleon coupling constant h_{πNN}^(1), as was asserted in our previous publications (hep-ph/0011230, nucl-th/0011100). In this comment we show that there is no solid evidence to support Zhu et al.'s claim. Moreover, we show that the subleading parity-violating coupling h_V cannot be extracted from observables at the order of interest based on the formalism of effective field theory.

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Jiunn-Wei Chen, Xiangdong Ji. 2001-01-25. Comment on "Subleading Corrections to Parity Violating Pion Photoproduction". https://arxiv.org/abs/hep-ph/0101290

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