Pion absorption on 3He and 4He with emission of three energetic protons
Abstract
Results from a 4π solid angle measurement of the reactions 3He(π+,ppp) and 4He(π+,ppp)n at incident pion energies of Tπ+=70, 118, 162, 239, and 330 MeV are presented. For 3He the total absorption cross sections and their decomposition into two-proton and three-proton components are evaluated; for 4He the three-proton absorption cross sections are given. The differential distributions of the three-proton multinucleon absorption mode of both nuclei are analyzed and compared to each other by making use of a complete set of variables. The data are investigated for signatures of initial and final state interactions: it is found that more than half of the three-proton yield cannot be accounted for by cascade mechanisms. The remaining strength shows dependence on the incident pion angular momentum, but also structures that are not explained by simple semiclassical models.
- Publication:
-
Physical Review C
- Pub Date:
- June 1997
- DOI:
- 10.1103/PhysRevC.55.2931
- Bibcode:
- 1997PhRvC..55.2931L
- Keywords:
-
- 25.80.Ls;
- 25.10.+s;
- 21.45.+v;
- 13.75.Gx;
- Pion inclusive scattering and absorption;
- Nuclear reactions involving few-nucleon systems;
- Few-body systems;
- Pion-baryon interactions