Parton Distribution Functions at the LHC

质子是由更基本的组分夸克和胶子组成的。这些参数作为他们携带的质子的动量的分数的函数，以及与他们相关联的散射过程的能量尺度。在微扰理论中，利用强耦合常数可以计算散射截面和部分子分布随能量标度的演化。然而，演化方程需要的输入是本质上非微扰的，必须参数化，并通过比较数据获得。该项目将涉及通过与大型强子对撞机（LHC）数据进行比较来改进这些部分子分布，并研究其对LHC进一步精确物理学的影响。这将涉及将各种新型过程纳入部分子提取和改进目前使用的理论框架。

The proton is made up of more fundamental constituents, quarks and gluons. These are parameterized as function of the fraction of the momentum of the proton they carry, and of the energy scale of the scattering process with which they are associated. The scattering cross sections and evolution of the parton distributions with energy scale can be calculated in perturbation theory using the strong coupling constant. However, the evolution equations need inputs which are intrinsically nonperturbative and have to be parameterized and obtained by comparison to data. The project will involve the improvement of these parton distributions by comparison to Large Hadron Collider (LHC) data and investigate the implications for further precision physics at the LHC. This will involve the inclusion of a variety of new types of processes into the parton extraction and improvements to the theoretical framework currently used.