Low-energy π NN system
Forschungszentrum Jülich, Institut für Kernphysik (Theorie) and
Julich Center for Hadron Physics, D-52425
2 Institute for Theoretical and Experimental Physics, B. Cheremushkinskaya 25, 117218 Moscow, Russia
a e-mail: email@example.com
The reaction NN → NNπ is studied at low energies within chiral perturbation theory (ChPT). Special emphasis is put on p-wave pion production in diﬀerent channels of NN → NNπ and Charge Symmetry Breaking (CSB) eﬀects in pn → dπ0 recently measured at TRIUMF. A very good agreement of the p-wave amplitudes with experimental observables demonstrates the applicability of ChPT to these reactions regardless the large momentum transfer. The results of a complete calculation of CSB eﬀects at leading order are presented. Based on this calculation we extract the strong contribution to the neutron-proton mass diﬀerence.
© Owned by the authors, published by EDP Sciences, 2010