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arXiv · 0910.0210

Electromagnetic effects in eta --> 3 pi

Christoph Ditsche·Bastian Kubis·Ulf-G. Meißner
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Abstract

We re-evaluate the electromagnetic corrections to eta --> 3 pi decays at next-to-leading order in the chiral expansion, arguing that effects of order e^2(m_d-m_u) disregarded so far are not negligible compared to other contributions of order e^2 times a light quark mass. Despite the appearance of the Coulomb pole in eta --> pi+ pi- pi0 and cusps in eta --> 3 pi0, the overall corrections remain small.

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Christoph Ditsche, Bastian Kubis, Ulf-G. Meißner. 2009-10-01. Electromagnetic effects in eta --> 3 pi. https://arxiv.org/abs/0910.0210

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