标题： 核子中π介子的过量证据 显示英文标题

标题： Evidence for excess pions in nuclei

摘要： 我们分析两种反应：小x下的电子产生和质子在核上的Drell-Yan产生。 我们表明，在电子产生中，如果正确考虑中间强子的虚度，核阴影效应会更大。 在Drell-Yan产生中，包含快部分子的初态相互作用。 有了这个输入，过量的π介子贡献改善了对这两种反应数据的描述。 显示英文摘要

摘要： 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 inter- mediate 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.