Effective field theory contribution to charge symmetry breaking NN scattering

Abstract

The effect of isospin breaking pion s-wave rescattering is included in elastic NN scattering at low energies using effective field theory. Although this mechanism gave a large contribution to charge symmetry breaking in np --> d pi0, the effect is rather small in pp vs. nn scattering parameters and in the 3H-3He binding energy difference. This smallness is caused by large cancellation of the up-down quark mass difference contribution and electromagnetic effects to the np mass difference.

Comments: 8 pages, 4 eps figures