Production of the 1S0 diproton in the pp -> pp pi0 reaction at 0.8 GeV

S. Dymov; D. Gusev; M. Hartmann; V. Hejny; A. Kacharava; A. Khoukaz; V. Komarov; P. Kulessa; A. Kulikov; V. Kurbatov; N. Lang; G. Macharashvili; T. Mersmann; S. Merzliakov; S. Mikirtytchiants; A. Mussgiller; D. Prasuhn; F. Rathmann; R. Schleichert; H. Stroeher; Yu. Uzikov; C. Wilkin; S. Yaschenko

doi:10.1016/j.physletb.2006.03.012

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Production of the 1S0 diproton in the pp -> pp pi0 reaction at 0.8 GeV

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Abstract

The pp -> pp pi0 differential cross section has been measured with the ANKE spectrometer at COSY-Juelich for pion cms angles between 0 and 15.4 degrees at a proton beam energy of 0.8 GeV. The selection of diproton pairs with an excitation energy E_{pp} < 3 MeV ensures that the final pp system is dominantly in the spin-singlet 1S0 state. The kinematics are therefore very similar to those of pp -> d pi+ but with different spin and isospin transitions. The results will thus provide a crucial extra test of pion production models in nucleon-nucleon collisions. The cross sections, which are over two orders of magnitude smaller than those of pp -> d pi+, show a forward dip, even stronger than that seen at lower energies. This behaviour is well reproduced in a theoretical model that includes P-wave Delta-N states.

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S. Dymov, D. Gusev, M. Hartmann, V. Hejny, A. Kacharava, A. Khoukaz, V. Komarov, P. Kulessa, A. Kulikov, V. Kurbatov, N. Lang, G. Macharashvili, T. Mersmann, S. Merzliakov, S. Mikirtytchiants, A. Mussgiller, D. Prasuhn, F. Rathmann, R. Schleichert, H. Stroeher, Yu. Uzikov, C. Wilkin, S. Yaschenko. 2005-12-22. Production of the 1S0 diproton in the pp -> pp pi0 reaction at 0.8 GeV. https://doi.org/10.1016/j.physletb.2006.03.012

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