论文标题
对光子波函数的非扰动QCD贡献的现象学分析
A phenomenological analysis of the nonperturbative QCD contributions for the photon wave function
论文作者
论文摘要
光子 - 诱导的交互作用，以$ EP $，$ ea $，$ pp $，$ pa $，$ aa $和$ e^+ e^ - $碰撞表示，在颜色偶极函数中表示，这描述了光子波函数，该函数描述了光子向Quark-Antiquark Color偶极偶极子的过渡。假设可以忽略与强相互作用相关的长距离校正，通常使用扰动理论计算这种数量。在本文中，我们研究了这些非扰动QCD（NPQCD）校正对大尺寸偶极子的描述在HERA，LEP和LHC测得的几种可观察到的偶极子的描述。我们假设一种现象学ANSATZ来处理这些NPQCD校正，并使用光生物生产横截面的实验数据来限制模型的自由参数。将$γγ$横截面的预测，$ EP $碰撞中的独家$ρ$生产以及$ PBPB $碰撞中$ρ$生产的速度分布与数据进行了比较。我们证明，包含非扰动QCD校正可以改善由大偶极子支配的过程的描述。
The photon -- induced interactions, present in $ep$, $eA$, $pp$, $pA$, $AA$ and $e^+ e^-$ collisions, are expressed within the color dipole approach in terms of the photon wave function, which describes the transition of the photon into a quark -- antiquark color dipole. Such quantity is usually calculated using perturbation theory assuming that long distance corrections associated to strong interactions can be neglected. In this paper we investigate the impact of these nonperturbative QCD (npQCD) corrections to the description of the photon wave function for dipoles of large size in several observables measured at HERA, LEP and LHC. We assume a phenomenological ansatz for the treatment of these npQCD corrections and constrain the free parameters of our model using the experimental data for the photoproduction cross section. The predictions for the $γγ$ cross section, exclusive $ρ$ production in $ep$ collisions and the rapidity distribution for the $ρ$ production in $PbPb$ collisions are compared with the data. We demonstrate that the inclusion of the nonperturbative QCD corrections improves the description of processes that are dominated by large dipoles.
