Parton Distribution Functions at the LHC

质子是由更基本的成分，夸克和胶子组成的。这些参数化为它们所携带的质子动量的分数的函数，以及与它们相关的散射过程的能量尺度的函数。在微扰理论中，利用强耦合常数可以计算出粒子在能量尺度上的散射截面和演化过程。然而，演化方程需要的输入本质上是非摄动的，并且必须参数化并通过与数据的比较来获得。该项目将涉及通过与大型强子对撞机（LHC）数据的比较来改进这些部分子分布，并研究LHC进一步精确物理的含义。这将涉及将各种新类型的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.