Perturbative nuclear physics

Abstract

We present a new formulation of effective field theory for nucleon-nucleon ($\mathit{NN}$) interactions that treats pion interactions perturbatively, and we offer evidence that the expansion converges satisfactorily to third order in the expansion, which we have computed analytically for $s$- and $d$-wave $\mathit{NN}$ scattering. Starting with the Kaplan-Savage-Wise (KSW) expansion about the nontrivial fixed point corresponding to infinite $\mathit{NN}$ scattering length, we cure the convergence problems with that theory by modifying the short distance pion interaction, essentially resumming those contributions in the contact interactions. This method appears to make possible a host of high precision analytic few-body calculations in nuclear physics.