Resonance-like structure$\bar pp$ annihilation into three π and the ππ correlations

Abstract

Experimental data of$\bar pp$ annihilation into 3π⁰ and π⁺π⁰π⁻ are analyzed in the quark pair creation model (³ P ₀ Model) with planar quark diagram topology. There are two form factors depending on whether 1) the two π′s contain a quark or an antiquark that originates from ap or a$\bar p$ respectively, or 2) one π contain a quark and an anti-quark both created from the vacuum. We call the amplitude of the first as a G-type and the latter as the an F-type. The intermediate states in G-type processes which contain correlations of the³ P ₀ vertices in the initial state and those in the final state can be regarded as gluons of 0⁺⁺ and a$\bar qq$. The two π resonance like structure of 0⁺⁺ (1520) observed in 3π⁰ and 2⁺⁺ observed in π⁺π⁰π⁻ can be interpreted as the interference of the G-type amplitudes with the F-type amplitudes.