Analysis of theJP=1+ and 0−three-pion systems

We analyze $3\pi$ production results obtained from recent diffractive and charge-exchange experiments. We find that two resonances, a $J^P=1^{+}\left(A_1\right)$ and a $J^P=0^{-}\left({\pi }^{\prime }\right)$ are required by the data. The resonance parameters are $M_{A_1}=1230\mathrm{}\pm 30$ MeV, ${\Gamma }_{A_1}=350\mathrm{}\pm 60$ MeV, and $M_{{\pi }^{\prime }}=1273\mathrm{}\pm 50$ MeV, ${\Gamma }_{{\pi }^{\prime }}=580\mathrm{}\pm 100$ MeV. We interpret the above resonances in terms of $q\overline{q}$ and $q^2{\overline{q}}^2$ quark-model states.