Improving the convergence of the chiral expansion for nuclear forces I: Peripheral phases

We study the two-pion exchange potential at next-to-next-to-leading order in chiral effective field theory. We propose a new cut–off scheme for the pion loop integrals based on spectral function regularization. We show that this method allows for a consistent implementation of constraints from pion–nucleon scattering. It leads to a much improved description of the partial waves with angular momentum l ≥ 2 as compared to the calculation utilizing dimensional regularization. email: [email protected] email: [email protected] email: [email protected]