${{\mathit \pi}^{+}}{{\mathit \pi}^{-}}{{\mathit \pi}^{0}}$ $/$ ${{\mathit \rho}}{{\mathit \pi}}$ AMPLITUDE RATIO ${{\mathit a}_{{{1}}}}$ IN DECAY OF $~{{\mathit \phi}}$ $\rightarrow$ ${{\mathit \pi}^{+}}{{\mathit \pi}^{-}}{{\mathit \pi}^{0}}$

INSPIRE   JSON  (beta) PDGID:
M004D1
NIECKNIG 2012 describes final-state interactions between the three pions in a dispersive framework using data on the ${{\mathit \pi}}{{\mathit \pi}}{\mathit P}{\mathrm -wave}$ scattering phase shift.
VALUE ($ 10^{-2} $) CL% EVTS DOCUMENT ID TECN  COMMENT
$\bf{ 9.1 \pm1.2}$ OUR AVERAGE
$10.1$ $\pm4.4$ $\pm1.7$ 80k 1
AKHMETSHIN
2006
CMD2 $1.017 - 1.021$ ${{\mathit e}^{+}}$ ${{\mathit e}^{-}}$ $\rightarrow$ ${{\mathit \pi}^{+}}{{\mathit \pi}^{-}}{{\mathit \pi}^{0}}$
$9.0$ $\pm1.1$ $\pm0.6$ 1.98M 2, 3
ALOISIO
2003
KLOE 1.02 ${{\mathit e}^{+}}$ ${{\mathit e}^{-}}$ $\rightarrow$ ${{\mathit \pi}^{+}}{{\mathit \pi}^{-}}{{\mathit \pi}^{0}}$
• • We do not use the following data for averages, fits, limits, etc. • •
$-6<\mathit a_{1}<6$ 500k 3
ACHASOV
2002
SND ${{\mathit e}^{+}}$ ${{\mathit e}^{-}}$ $\rightarrow$ ${{\mathit \pi}^{+}}{{\mathit \pi}^{-}}{{\mathit \pi}^{0}}$
$-16<{{\mathit a}_{{{1}}}}<11$ 90 9.8k 1, 4
AKHMETSHIN
1998
CMD2 ${{\mathit e}^{+}}$ ${{\mathit e}^{-}}$ $\rightarrow$ ${{\mathit \pi}^{+}}{{\mathit \pi}^{-}}{{\mathit \gamma}}{{\mathit \gamma}}$
1  Dalitz plot analysis taking into account interference between the contact and ${{\mathit \rho}}{{\mathit \pi}}$ amplitudes.
2  From a fit without limitations on charged and neutral ${{\mathit \rho}}~$masses and widths.
3  Recalculated by us to match the notations of AKHMETSHIN 1998.
4  Assuming zero phase for the contact term.
References