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arXiv · 1610.01207

Manifestation of the $P$-wave diproton resonance in single-pion production in $pp$ collisions

M. N. Platonova·V. I. Kukulin
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Abstract

It is demonstrated that many important features of single-pion production in $pp$ collisions at intermediate energies ($T_p \simeq 400$-$800$ MeV) can naturally be explained by supposing excitation of intermediate diproton resonances in $pp$ channels ${}^1D_2$, ${}^3F_3$ and ${}^3P_2$, in addition to conventional mechanisms involving an intermediate $\Delta$-isobar. We predict for the first time the crucial role of the ${}^3P_2$ diproton resonance, found in recent experiments on the single-pion production reaction $pp \to pp({}^1S_0) \pi^0$, in reproducing the proper behavior of spin-correlation parameters in the reaction $pp \to d \pi^+$ which were poorly described by conventional meson-exchange models to date. The possible quark structure of the $P$-wave diproton resonances is also discussed.

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M. N. Platonova, V. I. Kukulin. 2016-10-04. Manifestation of the $P$-wave diproton resonance in single-pion production in $pp$ collisions. https://doi.org/10.1103/physrevd.94.054039

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