Investigation of the dd→3Henπ0 reaction with the FZ Jülich WASA-at-COSY facility

Abstract

An exclusive measurement of the dd→3Henπ0 reaction was carried out at a beam momentum of pd= 1.2 GeV/c using the WASA-at-COSY facility. Information on the total cross section as well as differential distributions was obtained. The data are described by a phenomenological approach based on a combination of a quasifree model and a partial wave expansion for the three-body reaction. The total cross section is found to be σtot=(2.89±0.01stat±0. 06sys±0.29norm)μb. The contribution of the quasifree processes (with the beam or target neutron being a spectator) accounts for 38% of the total cross section and dominates the differential distributions in specific regions of phase space. The remaining part of the cross section can be described by a partial wave decomposition indicating the significance of p-wave contributions in the final state. © 2013 American Physical Society.