"Figure 12 bottom left" of "Search for long-lived particles decaying to a pair of muons in proton-proton collisions at $\sqrt{s}$ = 13 TeV"

Comparison of the number of events observed in 2018 data in the TMS-TMS dimuon category with the expected number of background events, in representative $m_{\mu \mu}$ intervals in the $6 < min(d_0 / \sigma_{d_0}) \leq 10$ bin. The black points with crosses show the number of observed events; the green and yellow components of the stacked histograms represent the estimated numbers of DY and QCD events, respectively. The last bin includes events in the overflow. The uncertainties in the total expected background (shaded area) are statistical only. Signal contributions expected from simulated $H \rightarrow Z_D Z_D$ with $m_{Z_D}$ of 20 and 50 GeV are shown in red and blue, respectively. Their yields are set to the corresponding combined median expected exclusion limits at 95% CL, scaled up as indicated in the legend to improve visibility. The legend also includes the total number of observed events as well as the number of expected background events obtained inclusively, by applying the background evaluation method to the events in all $m_{Z_D}$ and min($d_0 / \sigma_{d_0}$) intervals combined.

本图针对$6 < min(d_0/sigma_{d_0}) leq 10$分箱内的TMS-TMS双缪子类别，对比了2018年数据中观测到的事件数与预期本底事件数在代表性双缪子不变质量（$m_{mumu}$）区间内的分布情况。带叉号的黑色点代表观测事件数；堆叠直方图的绿色与黄色分量分别对应狄拉克-杨（Drell-Yan, DY）过程与量子色动力学（Quantum Chromodynamics, QCD）过程的预估事件数。最后一个分箱包含溢出事件。总预期本底的不确定度（阴影区域）仅为统计不确定度。由模拟得到的$H
ightarrow Z_D Z_D$（其中$m_{Z_D}$分别为20 GeV和50 GeV）的信号贡献分别以红色和蓝色展示，其产额被设置为对应95%置信度（Confidence Level, CL）下的联合中位数预期排除限，并按图例所示进行缩放以提升可视化效果。图例同时涵盖总观测事件数，以及通过将本底评估方法应用于所有$m_{Z_D}$与$min(d_0/sigma_{d_0})$区间的合并事件集所得到的总预期本底事件数。