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Radiation pions in two-nucleon effective field theory

Thomas Mehen·Iain W. Stewart
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Abstract

For interactions involving two or more nucleons it is useful to divide pions into three classes: potential, radiation, and soft. The momentum threshold for the production of radiation pions is $Q_r = \sqrt{M_N m_π}$. We show that radiation pions can be included systematically with a power counting in $Q_r$. The leading order radiation pion graphs which contribute to NN scattering are evaluated in the PDS and OS renormalization schemes and are found to give a small contribution. The power counting for soft pion contributions is also discussed.

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Thomas Mehen, Iain W. Stewart. 1999-08-21. Radiation pions in two-nucleon effective field theory. https://doi.org/10.1016/s0375-9474(99)00368-1

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