标题： 夸克在光子中的Ioffe时间分布 显示英文标题

标题： Ioffe-time distribution of quarks in the photon

摘要： 我们使用了相关函数的算符乘积展开来分析虚光子中夸克的Ioffe时间分布，该相关函数决定了相应夸克弦算符的矩阵元。 横向极化的光子的分布允许一种谱表示，这种表示可以延续到真实粒子区域$p^2 =0$。 所得的模型Ioffe时间分布比现有$F_2^{\gamma}$数据的参数化形式更大。 这一结果与原点处夸克分布的斜率有关，该斜率也显得过大。 显示英文摘要

摘要： We have analysed the Ioffe-time distribution of quarks in virtual photons using Operator Product Expansion of the correlation function that determines the matrix element of the corresponding quark string operator. The distribution for a transversally polarised photon admits a spectral representation which can be continued to the on-shell region $p^2 =0$. The resulting model Ioffe-time distribution turns out to be larger than parametrisations of the available $F_2^{\gamma}$ data. This result is linked to the slope of the quark distribution at the origin, which comes out too large as well.