Coupled channel analysis of $\pi^+\pi^-\pi^0$, $K^+ K^-\pi^0$ and $K^{\pm}K^0_S\pi^{\mp}$ from $\bar p p$ annihilation at rest in hydrogen targets at three densities

The OBELIX Collaboration

doi:doi:10.1140/epjc/s2002-01080-7

EPJ

Coupled channel analysis of $\pi^+\pi^-\pi^0$ , $K^+ K^-\pi^0$ and $K^{\pm}K^0_S\pi^{\mp}$ from $\bar p p$ annihilation at rest in hydrogen targets at three densities

The OBELIX Collaboration

Abstract
The $\pi^+\pi^-\pi^0$ , $K^+ K^-\pi^0$ and $K^\pm K^0 \pi^\mp$ final states produced by $\bar p p$ annihilation at rest at three different hydrogen target densities have been analyzed in the frame of a coupled channel analysis together with $\pi \pi$ , $\pi K$ and $K \bar K$ scattering data. The percentages of the different partial waves, the branching ratios and the parameters (masses, widths, $\pi \pi$ and $K \bar K$ partial widths) of all the involved resonances ( J^P=0⁺,1^-,2⁺) have been measured. The main results on meson spectroscopy concern the determination of the $\Gamma_{K \bar K}/\Gamma_{\pi \pi}$ ratio for f₀(1370) and f₀(1500) ( $\Gamma_{K \bar K}/\Gamma_{\pi \pi} = 0.91 \pm 0.20$ and $\Gamma_{K \bar K}/\Gamma_{\pi \pi} = 0.25 \pm 0.03$ respectively), the determination of a₀(1300) parameters ( $M=1303 \pm 16 \,$ MeV; $\Gamma= 92 \pm 16 \,$ MeV) and the observation of two different $\rho$ signals associated to $\rho(1450)$ and $\rho(1700)$ ( $M=1182 \pm 30 \,$ MeV; $\,\Gamma=389 \pm 20 \,$ MeV and $M=1594 \pm 20 \,$ MeV; $\,\Gamma=259 \pm 20 \,$ MeV respectively).

Società Italiana di Fisica, Springer-Verlag 2003