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A momentum subtraction scheme for two--nucleon effective field theory

Thomas Mehen·Iain W. Stewart
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Abstract

We introduce a momentum subtraction scheme which obeys the power counting of Kaplan, Savage, and Wise (KSW), developed for systems with large scattering lengths, $a$. Unlike the power divergence subtraction scheme, coupling constants in this scheme obey the KSW scaling for all $μ_R > 1/a$. We comment on the low-energy theorems derived by Cohen and Hansen. We conclude that there is no obstruction to using perturbative pions for momenta $p>m_π$.

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Thomas Mehen, Iain W. Stewart. 1998-09-22. A momentum subtraction scheme for two--nucleon effective field theory. https://doi.org/10.1016/s0370-2693(98)01470-1

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