| Mode | Fraction ($\Gamma_i$ / $\Gamma$) | Scale Factor/ Conf. Level |
P(MeV/c) | |||
| $\Gamma_{4}$ | ${{\mathit a}_{{1}}{(1640)}}$ $\rightarrow$ ${{\mathit \rho}}{{\mathit \pi}}$ $_{{\mathit S}{\mathrm -wave}}$ | seen | 638 | |||
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