P-wave dibaryon resonances in pp elastic scattering and near-threshold pion production

It is demonstrated within the dibaryon-induced model for $NN$ interaction that $pp$ scattering in $P$ waves is governed mainly by the production of the intermediate dibaryon resonances. Two dibaryon resonances with a mass of about 2200 MeV discovered recently by the ANKE-COSY Collaboration are shown to determine both elastic $pp$ phase shifts and inelasticities in the ${^{3}P}_{0}$ and ${^{3}P}_{2}$--${^{3}F}_{2}$ channels from zero energy up to ${T}_{p}=0.7--0.9\text{ }\mathrm{GeV}$. It is also demonstrated clearly that the ${^{3}P}_{0}$ dibaryon plays a decisive role in near-threshold neutral pion production in $pp$ collisions which is poorly understood to date. The missing dibaryon contribution is found to be the very possible reason for the failure of traditional approaches to explain near-threshold ${\ensuremath{\pi}}^{0}$ production.