Measurement Of Ann, Ano, And Aon For The Reaction Pp-]D-Pi+ In The Energy Region 500-800 Mev

Angular distributions of the spin observables ${A}_{\mathrm{nn}}$, ${A}_{\mathrm{no}}$, and ${A}_{\mathrm{on}}$ for the reaction pp\ensuremath{\rightarrow}d${\ensuremath{\pi}}^{+}$ have been measured for pion c.m. angles 30\ifmmode^\circ\else\textdegree\fi{}${\ensuremath{\theta}}_{\ensuremath{\pi}}^{\mathrm{*}}$110\ifmmode^\circ\else\textdegree\fi{} at beam kinetic energies of 500, 600, 650, 700, 733, and 800 MeV. These are precision data spanning the energy region of two conjectured dibaryon resonances in the NN system, one near 650 MeV ${(}^{1}$${\mathrm{D}}_{2}$) and one near 750 MeV ${(}^{3}$${\mathrm{F}}_{3}$). The ${A}_{\mathrm{nn}}$ data have a significant impact on the partial-wave analyses and are in disagreement with the predictions of existing models. The data show no direct evidence for the existence of either of the two dibaryon resonances.