We report an improved measurement of the valence 𝑢 and 𝑑 quark distributions from the forward-backward asymmetry in the Drell-Yan process using 8.6  fb−1 of data collected with the D0 detector in 𝑝⁢¯𝑝 collisions at √𝑠=1.96. This analysis provides the values of new structure parameters that are directly related to the valence up and down quark distributions in the proton. In other experimental results measuring the quark content of the proton, 𝑑 quark contributions are mixed with those from other quark flavors. In this measurement, the 𝑢 and 𝑑 quark contributions are separately extracted by applying a factorization of the QCD and electroweak portions of the forward-backward asymmetry.

中文翻译：

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质子的上下夸克结构


我们报告了在 Drell-Yan 过程中使用使用 D0 检测器在 √s=1.96 的 p ̄p 碰撞中收集的 8.6 fb−1 数据，改进了对 Drell-Yan 过程中前后不对称的价 u 和 d 夸克分布的测量.该分析提供了与质子中价上夸克和下夸克分布直接相关的新结构参数的值。在测量质子夸克含量的其他实验结果中，d 夸克的贡献与其他夸克风味的贡献混合。在此测量中，通过对 QCD 和前后不对称的电弱部分进行因式分解，分别提取 u 和 d 夸克贡献。