Harland-Lang L A, Martin A D, Motylinski P, Thorne R S
Department of Physics and Astronomy, University College London, London, WC1E 6BT UK.
Institute for Particle Physics Phenomenology, Durham University, Durham, DH1 3LE UK.
Eur Phys J C Part Fields. 2016;76(4):186. doi: 10.1140/epjc/s10052-016-4020-1. Epub 2016 Apr 6.
We investigate the effect of including the HERA run I + II combined cross section data on the MMHT2014 PDFs. We present the fit quality within the context of the global fit and when only the HERA data are included. We examine the changes in both the central values and the uncertainties in the PDFs. We find that the prediction for the data is good, and only relatively small improvements in [Formula: see text] and changes in the PDFs are obtained with a refit at both NLO and NNLO. PDF uncertainties are slightly reduced. There is a small dependence of the fit quality on the value of [Formula: see text]. This can be improved by phenomenologically motived corrections to [Formula: see text] which parametrically are largely in the form of higher-twist type contributions.
我们研究了将HERA第一阶段和第二阶段联合截面数据纳入MMHT2014部分子分布函数（PDFs）的影响。我们展示了在全局拟合背景下以及仅包含HERA数据时的拟合质量。我们研究了PDFs中心值和不确定性的变化。我们发现对数据的预测良好，在NLO和NNLO进行重新拟合时，仅在[公式：见原文]方面有相对较小的改进以及PDFs有变化。PDFs的不确定性略有降低。拟合质量对[公式：见原文]的值有轻微依赖性。这可以通过对[公式：见原文]进行唯象动机修正来改善，这些修正参数上主要以高扭度类型贡献的形式出现。
