### 抜粋

We reassess the validity of the current-algebra based low-energy theorem of pion photoproduction on the nucleon using the Skyrme model. We find that one of the off-shell electromagnetic form factors of the nucleon exhibits infrared divergence in the chiral limit. This contribution introduces an additional term to the threshold amplitude predicted by the low-energy theorem. The emergence of the additional term indicates an unavoidable necessity of off-shell form factors in deriving the low-energy theorem. In the case of neutral pion production, the new contribution to the threshold amplitude is found to be comparable in magnitude to the low-energy theorem's prediction and has the opposite sign. In the charged pion production channels, the correction to the theorem is shown to be relatively small.

元の言語 | English |
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ページ（範囲） | 443-471 |

ページ数 | 29 |

ジャーナル | Nuclear Physics, Section A |

巻 | 592 |

発行部数 | 4 |

DOI | |

出版物ステータス | Published - 1995 10 2 |

外部発表 | Yes |

### フィンガープリント

### ASJC Scopus subject areas

- Nuclear and High Energy Physics

### これを引用

*Nuclear Physics, Section A*,

*592*(4), 443-471. https://doi.org/10.1016/0375-9474(95)00325-U