Energy dependence of forward 1S0 diproton production in the pp -> pp pi0 reaction

Abstract

The pp -> {pp}_s pi0 differential cross section has been measured with the ANKE spectrometer at COSY-Juelich for seven proton beam energies T_p between 0.5 and 1.97 GeV. By selecting proton pairs with an excitation energy of less than 3 MeV it is ensured that the final {pp}_s system is in the 1S0 state. In the measured region of theta_{pp}^{cm} < 18 deg, the data reveal a forward dip for T_p =< 1.4 GeV whereas a forward peaking is seen at 1.97 GeV. The energy dependence of the forward cross section shows a broad peak in the 0.6-0.8 GeV region, probably associated with Delta(1232) excitation, and a minimum at 1.4 GeV. Some of these features are similar to those observed for the spin-isospin partner reaction, pp -> d pi+. However, the ratio of the forward differential cross sections of the two reactions shows a significant suppression of single pion production associated with a spin--singlet final nucleon pair.

arXiv comment12 pages, 4 figures

References in corpus (11)

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Cited by in corpus (6)

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• Impacts of Hawking Radiation from Primordial Black Holes in Critical Collapse Model on the Light Element Abundances
• Observation of inverse diproton photodisintegration at intermediate energies
• Differential cross section and analysing power of the pp -> {pp\}_s pi0 reaction at 353 MeV
• Resonance-like coherent production of a pion pair in the reaction $pd\to pd\pi \pi$ in the GeV region
• Resonant behavior of the $pp\to \{pp{\}}_s{\pi }^0$ reaction at the energy $\sqrt{s}$ = 2.65 GeV