Mass and width of sigma(750) scalar meson from measurements of pi(-)p->pi(-)pi(+)n on polarized target

Abstract

Model independent amplitude analyses of $\ddot{I}{€}^{-}{p}_{\uparrow }\to \ddot{I}{€}^{-}\ddot{I}{€}^{+}n$ on polarized target at 17.2 GeV/c reveal resonant structure of S-wave transversity amplitudes $|\bar{S}{|}^2\hat{I}\pounds$ and $|S{|}^2\hat{I}\pounds$ near 750 MeV. Simultaneous fit to $|\bar{S}{|}^2\hat{I}\pounds$ and $|S{|}^2\hat{I}\pounds$ with a single $\ddot{I}ƒ$ pole yields $m_{\ddot{I}}ƒ=775\pm 17$ MeV and $\hat{I}{“}_{\ddot{I}}ƒ=147\pm 33$ MeV. Simultaneous fit with two common $\ddot{I}ƒ$ poles yields a lower $\ddot{I}{‡}^2/dpt$. Their resonance parameters are $m_{\ddot{I}}ƒ=786\pm 24$ MeV, $\hat{I}{“}_{\ddot{I}}ƒ=130\pm 47$ MeV and $m_{\ddot{I}{ƒ}^{\prime }}=670\pm 30$ MeV, $\hat{I}{“}_{\ddot{I}{ƒ}^{\prime }}=59\pm 58$ MeV.

4 pages, 3 figures