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Pions in the Pionless Effective Field Theory

Silas R. Beane·Martin J. Savage
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Abstract

We show that processes involving pions that remain very near their mass-shell can be reliably computed in the pionless effective field theory, with the pion integrated in as a heavy field. As an application, we compute the pion-deuteron scattering amplitude near threshold to next-to-leading order in the momentum expansion. This amplitude is formally dominated by an infrared logarithm of the form log(gamma/mpi), where gamma is the deuteron binding momentum, and mpi is the mass of the pion. The coefficient of this logarithm is determined by the S-wave pion-nucleon scattering lengths.

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Silas R. Beane, Martin J. Savage. 2002-05-13. Pions in the Pionless Effective Field Theory. https://doi.org/10.1016/s0375-9474(03)00594-3

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