ABSOLUTE CROSS-SECTIONS FOR THE C-12(PI+/-,PI-N)C-11 REACTIONS BETWEEN 40 AND 600 MEV

The excitation functions for the C12(π±,πN)C11 reactions have been established for 40- to 600-MeV π- and 50- to 520-MeV π+. These excitation functions are dominated by the (3,3) pion-nucleon resonance but show an upward energy shift in the resonance peak for π- (to about 190 MeV) and a downward shift for π+ (to about 160 MeV). The σ(π-)σ(π+) ratio at 180 MeV is 1.59±0.07. The results are compared with theoretical calculations based on a semiclassical transport model including nucleon charge exchange and an intranuclear cascade model. NUCLEAR REACTIONS C12(π±,πN)C11, excitation functions, Eπ+=50-520 MeV, Eπ-=40-600 MeV. Plastic scintillator targets, measured C11 by β+-γ coincidences. Compared with semiclassical transport and intranuclear cascade calculations. © 1979 The American Physical Society.