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${{\mathit \rho}{(770)}}$ WIDTH

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CHARGED ONLY, ${{\mathit \tau}}$ DECAYS and ${{\mathit e}^{+}}{{\mathit e}^{-}}$

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M009W5

VALUE (MeV) EVTS DOCUMENT ID TECN CHG  COMMENT $\bf{ 149.1 \pm0.8}$ OUR FIT $\bf{ 149.1 \pm0.8}$ OUR AVERAGE $148.1$ $\pm0.4$ $\pm1.7$ 5.4M 1, 2 FUJIKAWA 2008 BELL $\pm{}$ ${{\mathit \tau}^{-}}$ $\rightarrow$ ${{\mathit \pi}^{-}}{{\mathit \pi}^{0}}{{\mathit \nu}_{{\tau}}}$ $149.0$ $\pm1.2$ 2, 3 SCHAEL 2005 C ALEP ${{\mathit \tau}^{-}}$ $\rightarrow$ ${{\mathit \pi}^{-}}{{\mathit \pi}^{0}}{{\mathit \nu}_{{\tau}}}$ $149.9$ $\pm2.3$ $\pm2.0$ 500k 4 ACHASOV 2002 SND $\pm{}$ 1.02 ${{\mathit e}^{+}}$ ${{\mathit e}^{-}}$ $\rightarrow$ ${{\mathit \pi}^{+}}{{\mathit \pi}^{-}}{{\mathit \pi}^{0}}$ $150.4$ $\pm1.4$ $\pm1.4$ 87k 5, 6 ANDERSON 2000 A CLE2 ${{\mathit \tau}^{-}}$ $\rightarrow$ ${{\mathit \pi}^{-}}{{\mathit \pi}^{0}}{{\mathit \nu}_{{\tau}}}$ • • We do not use the following data for averages, fits, limits, etc. • • $139.90$ $\pm0.46$ 7 BARTOS 2017 A RVUE ${{\mathit \tau}^{-}}$ $\rightarrow$ ${{\mathit \pi}^{-}}{{\mathit \pi}^{0}}{{\mathit \nu}_{{\tau}}}$ $143.7$ $\pm1.3$ $\pm1.2$ 1.98M 4 ALOISIO 2003 KLOE $\pm{}$ 1.02 ${{\mathit e}^{+}}$ ${{\mathit e}^{-}}$ $\rightarrow$ ${{\mathit \pi}^{+}}{{\mathit \pi}^{-}}{{\mathit \pi}^{0}}$ $142.9$ $\pm1.3$ $\pm1.4$ 1.98M 8 ALOISIO 2003 KLOE - 1.02 ${{\mathit e}^{+}}$ ${{\mathit e}^{-}}$ $\rightarrow$ ${{\mathit \pi}^{+}}{{\mathit \pi}^{-}}{{\mathit \pi}^{0}}$ $144.7$ $\pm1.4$ $\pm1.2$ 1.98M 8 ALOISIO 2003 KLOE + 1.02 ${{\mathit e}^{+}}$ ${{\mathit e}^{-}}$ $\rightarrow$ ${{\mathit \pi}^{+}}{{\mathit \pi}^{-}}{{\mathit \pi}^{0}}$ $150.2$ $\pm2.0$ ${}^{+0.7}_{-1.6}$ 9 SANZ-CILLERO 2003 RVUE ${{\mathit \tau}^{-}}$ $\rightarrow$ ${{\mathit \pi}^{-}}{{\mathit \pi}^{0}}{{\mathit \nu}_{{\tau}}}$ $150.9$ $\pm2.2$ $\pm2.0$ 500k 10 ACHASOV 2002 SND 1.02 ${{\mathit e}^{+}}$ ${{\mathit e}^{-}}$ $\rightarrow$ ${{\mathit \pi}^{+}}{{\mathit \pi}^{-}}{{\mathit \pi}^{0}}$ 1  $\vert \mathit F_{{{\mathit \pi}}}(0)\vert ^2$ fixed to 1. 2  From the GOUNARIS 1968 parametrization of the pion form factor. 3  The error combines statistical and systematic uncertainties. Supersedes BARATE 1997M. 4  Assuming ${\mathit m}_{{{\mathit \rho}^{+}}}$ = ${\mathit m}_{{{\mathit \rho}^{-}}}$, $\Gamma _{{{\mathit \rho}^{+}}}$ = $\Gamma _{{{\mathit \rho}^{-}}}$. 5  ${{\mathit \rho}{(1700)}}$ mass and width fixed at 1700 MeV and 235 MeV respectively. 6  From the GOUNARIS 1968 parametrization of the pion form factor. The second error is a model error taking into account different parametrizations of the pion form factor. 7  Applies the Unitary $\&$ Analytic Model of the pion electromagnetic form factor of DUBNICKA 2010 to analyze the data of FUJIKAWA 2008 . 8  Without limitations on masses and widths. 9  Using the data of BARATE 1997M and the effective chiral Lagrangian. 10  Assuming ${\mathit m}_{{{\mathit \rho}^{0}}}$ = ${\mathit m}_{{{\mathit \rho}^{\pm}}}$, $\mathit g_{ {{\mathit \rho}^{0}} {{\mathit \pi}} {{\mathit \pi}} }$ = $\mathit g_{ {{\mathit \rho}^{\pm}} {{\mathit \pi}} {{\mathit \pi}} }$.

References:

BARTOS 2017A IJMP A32 1750154 The Mass and Width Differences of the Neutral and Charged ${{\mathit \rho}{(770)}}$, ${{\mathit \rho}{(1450 )}}$ and ${{\mathit \rho}{(1700)}}$ Mesons from ${{\mathit e}^{+}}$ ${{\mathit e}^{-}}$ $\rightarrow$ ${{\mathit \pi}^{+}}{{\mathit \pi}^{-}}$ and ${{\mathit \nu}}{{\mathit \tau}}{{\mathit \pi}^{-}}{{\mathit \pi}^{0}}$ Processes FUJIKAWA 2008 PR D78 072006 High-Statistics Study of the Decay SCHAEL 2005C PRPL 421 191 Branching Ratios and Spectral Functions of ${{\mathit \tau}}$ Decays: Final ALEPH Measurements and Physics Implications ALOISIO 2003 PL B561 55 Study of the Decay ${{\mathit \phi}}$ $\rightarrow$ ${{\mathit \pi}^{+}}{{\mathit \pi}^{-}}{{\mathit \pi}^{0}}$ with the Detector SANZ-CILLERO 2003 EPJ C27 587 ${{\mathit \rho}}$ Meson Properties in the Chiral Theory Framework ACHASOV 2002 PR D65 032002 Study of the ${{\mathit \pi}}{{\mathit \pi}}$ Mass Spectra in the Process ${{\mathit e}^{+}}$ ${{\mathit e}^{-}}$ $\rightarrow$ ${{\mathit \pi}^{+}}{{\mathit \pi}^{-}}{{\mathit \pi}^{0}}$ at $\sqrt {s }$ = 1020 MeV ANDERSON 2000A PR D61 112002 Hadronic Structure in the Decay ${{\mathit \tau}^{-}}$ $\rightarrow$ ${{\mathit \pi}^{-}}{{\mathit \pi}^{0}}{{\mathit \nu}_{{\tau}}}$

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