Role of ∆ exchange for pp̄ annihilation into two - pion and three - pion channels
نویسندگان
چکیده
Role of ∆ exchange for p¯ p annihilation into two-pion and three-pion channels Abstract p¯ p annihilation into two pions and three pions is studied in a baryon-exchange model. Annihilation diagrams involving nucleon as well as ∆-resonance exchanges are included consistently in the two-and three-pion channels. Effects from the initial-state interaction are fully taken into account. A comparison of the influence of the ∆ exchange on the considered annihilation channels is made and reveals that its importance for three-pion annihilation is strongly reduced as compared to two-pion annihilation. It is found that annihilation into three uncorrelated pions can yield up to 10% of the total experimentally observed three-pion annihilation cross section.
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