p-wave pion production from nucleon-nucleon collisions

We investigate p-wave pion production in nucleon-nucleon collisions up to next-to-next-to-leading order in chiral effective field theory. In particular, we show that it is possible to describe simultaneously the p-wave amplitudes in the pn -> pp pi(-), pp -> pn pi(+), pp -> d pi(+) channels by adjusting a single low-energy constant accompanying the short-range operator that is available at this order. This study provides a nontrivial test of the applicability of chiral effective field theory to reactions of the type NN -> NN pi.