A momentum subtraction scheme for two–nucleon effective field theory
نویسندگان
چکیده
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 μR > 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 > mπ.
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