6533b853fe1ef96bd12ac06e

RESEARCH PRODUCT

K¯-induced formation of thef0(980)anda0(980)resonances on proton targets

subject

description

We perform a calculation of the cross section for nine reactions induced by $\overline{K}$ scattering on protons. The reactions studied are ${K}^{\ensuremath{-}}p\ensuremath{\rightarrow}\mathrm{\ensuremath{\Lambda}}{\ensuremath{\pi}}^{+}{\ensuremath{\pi}}^{\ensuremath{-}}$, ${K}^{\ensuremath{-}}p\ensuremath{\rightarrow}{\mathrm{\ensuremath{\Sigma}}}^{0}{\ensuremath{\pi}}^{+}{\ensuremath{\pi}}^{\ensuremath{-}}$, ${K}^{\ensuremath{-}}p\ensuremath{\rightarrow}\mathrm{\ensuremath{\Lambda}}{\ensuremath{\pi}}^{0}\ensuremath{\eta}$, ${K}^{\ensuremath{-}}p\ensuremath{\rightarrow}{\mathrm{\ensuremath{\Sigma}}}^{0}{\ensuremath{\pi}}^{0}\ensuremath{\eta}$, ${K}^{\ensuremath{-}}p\ensuremath{\rightarrow}{\mathrm{\ensuremath{\Sigma}}}^{+}{\ensuremath{\pi}}^{\ensuremath{-}}\ensuremath{\eta}$, ${\overline{K}}^{0}p\ensuremath{\rightarrow}\mathrm{\ensuremath{\Lambda}}{\ensuremath{\pi}}^{+}\ensuremath{\eta}$, ${\overline{K}}^{0}p\ensuremath{\rightarrow}{\mathrm{\ensuremath{\Sigma}}}^{0}{\ensuremath{\pi}}^{+}\ensuremath{\eta}$, ${\overline{K}}^{0}p\ensuremath{\rightarrow}{\mathrm{\ensuremath{\Sigma}}}^{+}{\ensuremath{\pi}}^{+}{\ensuremath{\pi}}^{\ensuremath{-}}$, and ${\overline{K}}^{0}p\ensuremath{\rightarrow}{\mathrm{\ensuremath{\Sigma}}}^{+}{\ensuremath{\pi}}^{0}\ensuremath{\eta}$. We find that in the reactions producing ${\ensuremath{\pi}}^{+}{\ensuremath{\pi}}^{\ensuremath{-}}$, a clear peak for the ${f}_{0}(980)$ resonance is found, while no trace of ${f}_{0}(500)$ appears. Similarly, in the cases of $\ensuremath{\pi}\ensuremath{\eta}$ production, a strong peak is found for the ${a}_{0}(980)$ resonance, with the characteristic strong cusp shape. Cross sections and invariant mass distributions are evaluated which should serve, by comparing them with future data, to test the dynamics of the chiral unitary approach used for the evaluations and the nature of these resonances.