2π0Mass Spectrum andδ00fromπ−+p→π0+nat 10GeVc

Abstract

An enhancement in the $2{\ensuremath{\pi}}^{0}$ mass spectrum in the region ${M}_{\ensuremath{\pi}\ensuremath{\pi}}<1$ GeV has been observed in ${\ensuremath{\pi}}^{\ensuremath{-}}+p\ensuremath{\rightarrow}{\ensuremath{\pi}}^{0}+{\ensuremath{\pi}}^{0}+n$ at 10 $\frac{\mathrm{GeV}}{c}$. This is interpreted as a broad isospin-0, $s$-wave resonance at 600\ifmmode\pm\else\textpm\fi{}100 MeV with width 400\ifmmode\pm\else\textpm\fi{}100 MeV. Because of limited mass resolution, we cannot rule out several narrower resonances with these quantum numbers.