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Isospin violation in the two-nucleon system

E. Epelbaum·Ulf-G. Meißner
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Abstract

I discuss isospin violation in an effective field theory appraoch of the nucleon-nucleon interaction. The observed leading order charge independence breaking is explained in terms of one-pion exchange together with a four-nucleon contact term. A general classification scheme of corrections to this leading order results is presented and an explanation is offered why charge-dependent pion-nucleon coupling constants can not play a role in the observed isospin violation in the NN scattering lengths. Charge symmetry breaking, the size of $πγ$-exchange graphs and the pionless theory are also discussed.

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E. Epelbaum, Ulf-G. Meißner. 1999-03-25. Isospin violation in the two-nucleon system. https://arxiv.org/abs/nucl-th/9903046

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