A Momentum subtraction scheme for two nucleon effective field theory

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 .