Article ID | Journal | Published Year | Pages | File Type |
---|---|---|---|---|
8192654 | Physics Letters B | 2011 | 9 Pages |
Abstract
Exclusive measurements of the ppâppÏ0Ï0 reaction have been performed at CELSIUS/WASA at energies from threshold up to Tp=1.3 GeV. Total and differential cross sections have been obtained. Here we concentrate on energies Tp⩾1 GeV, where the ÎÎ excitation becomes the leading process. No evidence is found for a significant ABC effect beyond that given by the conventional t-channel ÎÎ excitation. This holds also for the double-pionic fusion to the quasibound 2He. The data are compared to model predictions, which are based on both Ï- and Ï-exchange. Total and differential cross sections are at variance with these predictions and call for a profound modification of the Ï-exchange. A phenomenological modification allowing only a small Ï-exchange contribution leads to a quantitative description of the data.
Keywords
Related Topics
Physical Sciences and Engineering
Physics and Astronomy
Nuclear and High Energy Physics
Authors
T. Skorodko, M. Bashkanov, D. Bogoslawsky, H. Calén, H. Clement, E. Doroshkevich, L. Demiroers, C. Ekström, K. Fransson, L. Gustafsson, B. Höistad, G. Ivanov, M. Jacewicz, E. Jiganov, T. Johansson, O. Khakimova, S. Keleta, I. Koch, J. Zlomanczuk,