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ENERGY DEPENDENCE OF ${{\mathit K}^{\pm}}$ DALITZ PLOT

$\vert $matrix element$\vert ^2$ = 1 + $\mathit g{}\mathit u$ + $\mathit h{}\mathit u{}^{2}$ + $\mathit k{}\mathit v{}^{2}$ where $\mathit u$ = ($\mathit s_{3}$ $−$ $\mathit s_{0}$) $/$ ${{\mathit m}^{2}}_{{{\mathit \pi}}}$ and $\mathit v$ = ($\mathit s_{2}$ $−$ $\mathit s_{1}$) $/$ ${{\mathit m}^{2}}_{{{\mathit \pi}}}$

QUADRATIC COEFFICIENT $\mathit k$ FOR ${{\mathit K}^{\pm}}$ $\rightarrow$ ${{\mathit \pi}^{\pm}}{{\mathit \pi}^{+}}{{\mathit \pi}^{-}}$

INSPIRE   PDGID:

S010KT

VALUE ($ 10^{-3} $) EVTS DOCUMENT ID TECN CHG $-4.63$ $\pm0.14$ 471M 1 BATLEY 2007 B NA48 $\pm{}$ • • We do not use the following data for averages, fits, limits, etc. • • $-20.5$ $\pm3.9$ 225k DEVAUX 1977 SPEC + $-7.5$ $\pm1.9$ 750k FORD 1972 ASPK + $-8.3$ $\pm1.9$ 750k FORD 1972 ASPK - $-10.5$ $\pm4.5$ 39819 HOFFMASTER 1972 HLBC + $-14$ $\pm12$ 50919 MAST 1969 HBC - 1  Final state strong interaction and radiative corrections not included in the fit.

References:

BATLEY 2007B PL B649 349 Measurement of the Dalitz Plot Slope Parameters of the ${{\mathit K}^{\pm}}$ $\rightarrow$ ${{\mathit \pi}^{\pm}}{{\mathit \pi}^{+}}{{\mathit \pi}^{-}}$ Decay DEVAUX 1977 NP B126 11 A Study of 225000 ${{\mathit \tau}^{+}}$ Decays FORD 1972 PL 38B 335 Experimental Study on the ${{\mathit \tau}^{\pm}}$ Decay Matrix Element HOFFMASTER 1972 NP B36 1 Analysis of the Pion Spectrum of 39819 ${{\mathit \tau}^{+}}$ Decays at Rest MAST 1969 PR 183 1200 51000 ${{\mathit \tau}^{-}}$ Decays

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