【摘要】 通过p A碰撞的核Drell Yan过程研究了核遮蔽效应及其空间相关性.对末态轻子对的观测反映了相互作用点的情况.计算了能量为800 GeV的质子打击Ca,W,Au核的Drell Yan过程与p p碰撞Drell Yan过程的微分截面比.研究发现,在考虑部分子分布的空间依赖性后,核Drell Yan的截面会有显著变化.计算结果与未来精确测量p A碰撞核Drell Yan过程的实验数据比较,能够定量地验证部分子分布函数的空间依赖性.更多还原

【Abstract】 The nuclear shadowing effect and its position dependence are studied by the p-A DrellYan process.The nuclear DrellYan process can be used to study the spatial dependence of parton distribution functions.The dileptons produced in Drell-Yan process don’t interact with other partons in the nuclear.Therefore,the final-states dileptons can infer the information of local partons.Considering the spatial dependence of parton distribution functions,the p-A DrellYan cross-section can be written as follows.With two kinds of spatial dependent shadowing parameterizations given in literature:the Drell-Yan cross-section ratios for an 800*!GeV proton beam incident on p,Ca,W and Au are calculated.It is found that,considering the spatial dependence of parton distribution functions,the cross-section of nuclear DrellYan process changes significantly.By Comparing our result with the future precise data measured in Drell-Yan process,the spatial dependent parton distribution functions can be examined.更多还原