标题： CMS PYTHIA 8 色重联调优基于基础事件数据 显示英文标题

标题： CMS PYTHIA 8 colour reconnection tunes based on underlying-event data

摘要： 针对PYTHIA 8事件生成器中实现的两种颜色重连模型——量子色动力学启发模型和胶子移动模型，基于默认的CMS PYTHIA 8底层事件调优CP5，获得了新的参数调优。 由CMS实验在质心系能量$\sqrt{s}$ = 7和13 TeV，以及由CDF实验在1.96 TeV下进行的对底层事件敏感的测量结果，被用来同时约束颜色重连模型和多部分子相互作用的参数。 新的颜色重连调优与1.96、7、8和13 TeV下的各种测量结果进行了比较，包括底层事件、奇异粒子多重性、喷注子结构可观测量、喷注形状以及顶夸克对（$\mathrm{t\bar{t}}$）事件中的颜色流的测量结果。 这些新的调优也被用于估计在使用13 TeV半轻子道中$\mathrm{t\bar{t}}$事件的衰变产物进行顶夸克质量测量时，与颜色重连建模相关的不确定性。 显示英文摘要

摘要： New sets of parameter tunes for two of the colour reconnection models, quantum chromodynamics-inspired and gluon-move, implemented in the PYTHIA 8 event generator, are obtained based on the default CMS PYTHIA 8 underlying-event tune, CP5. Measurements sensitive to the underlying event performed by the CMS experiment at centre-of-mass energies $\sqrt{s}$ = 7 and 13 TeV, and by the CDF experiment at 1.96 TeV are used to constrain the parameters of colour reconnection models and multiple-parton interactions simultaneously. The new colour reconnection tunes are compared with various measurements at 1.96, 7, 8, and 13 TeV including measurements of the underlying-event, strange-particle multiplicities, jet substructure observables, jet shapes, and colour flow in top quark pair ($\mathrm{t\bar{t}}$) events. The new tunes are also used to estimate the uncertainty related to colour reconnection modelling in the top quark mass measurement using the decay products of $\mathrm{t\bar{t}}$ events in the semileptonic channel at 13 TeV.