Measurement of the underlying event activity in inclusive Z boson production in proton-proton collisions at $\sqrt{s} = $ 13 TeV

This paper presents a measurement of the underlying event activity in proton-proton collisions at a center-of-mass energy of 13 TeV, performed using inclusive Z boson production events collected with the CMS experiment at the LHC. The analyzed data correspond to an integrated luminosity of 2.1 fb$^{-1}$. The underlying event activity is quantified in terms of the charged particle multiplicity, as well as of the scalar sum of the charged particles' transverse momenta in different topological regions defined with respect to the Z boson direction. The distributions are unfolded to the stable particle level and compared with predictions from various Monte Carlo event generators, as well as with similar CDF and CMS measurements at center-of-mass energies of 1.96 and 7 TeV respectively.

本文介绍了使用LHC上的CMS实验收集的包含Z玻色子生产事件进行的质子 - 质子碰撞中的基础事件活动。分析的数据对应于2.1 fb $^{ - 1} $的集成光度。基础事件活性是根据带电的粒子多样性以及在不同拓扑区域定义的Z玻孔方向定义的不同拓扑区域的带电粒子横向动量的标量总和来量化的。将分布展开至稳定的粒子水平，并与各种Monte Carlo事件发生器的预测以及分别在1.96和7 TEV的质量中心能量下的CDF和CMS测量值进行比较。