标题： LEP2上强子光子结构函数F_2^gamma的测量 显示英文标题

标题： Measurement of the Hadronic Photon Structure Function F_2^gamma at LEP2

摘要： 光子的强子结构函数 F_2^gamma 在 Bjkren x 和分解尺度 Q^2 的函数关系上进行测量，使用的是 LEP 上 OPAL 探测器采集的数据。 OPAL 之前对 F_2^gamma 的 x 依赖性的测量扩展到了平均 Q^2 为 767 GeV^2。 在平均 Q^2 介于 11.9 到 1051 GeV^2 范围内研究了 F_2^gamma 的 Q^2 演化。 正如 QCD 预测的那样，数据显示出 F_2^gamma 中的正标度违反。 几种 F_2^gamma 的参数化与测量结果一致，而夸克-部分子模型的预测无法描述数据。 显示英文摘要

摘要： The hadronic structure function of the photon F_2^gamma is measured as a function of Bjorken x and of the factorisation scale Q^2 using data taken by the OPAL detector at LEP. Previous OPAL measurements of the x dependence of F_2^gamma are extended to an average Q^2 of 767 GeV^2. The Q^2 evolution of F_2^gamma is studied for average Q^2 between 11.9 and 1051 GeV^2. As predicted by QCD, the data show positive scaling violations in F_2^gamma. Several parameterisations of F_2^gamma are in agreement with the measurements whereas the quark-parton model prediction fails to describe the data.