F eb 1 99 5 Evidence for Excess Pions in Nuclei
نویسنده
چکیده
We analize two reactions: the electroproduction at small x and the Drell-Yan production by protons on nuclei. We show that nuclear shadowing in electroproduction is larger if the virtuality of intermediate hadrons is properly taken into account. In the Drell-Yan production, initial state interactions of fast partons are included. With this input, the excess pion contribution improves the description of data for both reactions.
منابع مشابه
O ct 1 99 4 SUNY - NTG - 94 - 54 October 1994 WHERE THE NUCLEAR PIONS ARE
Three recent experiments, which looked at pionic effects in nuclei have concluded that there are no excess pions. This puts into serious question the conventional meson-exchange picture of the nucleon-nucleon interaction. Based on arguments of partial restoration of chiral symmetry with density we propose a resolution to this problem.
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