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arXiv · 0812.4661

Dynamics of 1S0 diproton formation in the reactions pp-> (pp)_s+pi0$ and pp-> (pp)_s+gamma in the GeV region

Yu. N. Uzikov
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Abstract

COSY-ANKE data on the cross section of the reactions $pp\to \{pp\}_sπ^0$ and $pp\to \{pp\}_sγ$, where $\{pp\}_s$ is the proton pair in the $^1S_0$ state at small excitation energy $E_{pp}<3$ MeV, are analyzed at beam energies $0.5 - 2.0$ GeV within the one-pion exchange model. The model includes the subprocesses $π^0 p\to π^0 p$ and $π^0 p\to γp$ for the pion- and photo-production, respectively, and accounts for the final state pp-interaction. A broad maximum in the energy dependence of the $π^0$ production at $\sim 0.5 -0.6$ GeV and fast increase of the $γ$-production cross section at $0.3 - 0.55$ GeV observed in the data are explained by the $Δ$-isobar contribution. An analogy with the dynamics of the deuteron breakup reaction $pd\to \{pp\}_sn$ in the $Δ$-region is outlined.

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Yu. N. Uzikov. 2008-12-26. Dynamics of 1S0 diproton formation in the reactions pp-> (pp)_s+pi0$ and pp-> (pp)_s+gamma in the GeV region. https://arxiv.org/abs/0812.4661

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