"Figure 4 - bottom left, low pt DeepTau vs jet" of "Identification of hadronic tau lepton decays using a deep neural network"

Efficiency for quark and gluon jets to pass different tau identification discriminators versus the efficiency for genuine tau_h. The upper two plots are obtained with jets from the W+jets simulated sample and the lower two plots with jets from the tt sample. The left two plots include jets and genuine tau_h with pt < 100 GeV, whereas the right two plots include those with pt > 100 GeV. The working points are indicated as full circles. The efficiency for jets from the W+jets event sample, enriched in quark jets, to pass the discriminators is higher compared to jets from the tt event sample, which has a larger fraction of gluon and b-quark jets. The jet efficiency for a given tau_h efficiency is larger for jets and tau_h with pt < 100 GeV than for those with pt > 100 GeV. Compared with the previously used MVA discriminator, the DEEPTAU discriminator reduces the jet efficiency for a given tau_h efficiency by consistently more than a factor of 1.8, and by more at high tau_h efficiency. The additional gain at high pt comes from the inclusion of updated decay modes in the tau_h reconstruction, as illustrated by the curves for the previously used MVA discriminator but including reconstructed tau_h candidates with additional decay modes.

夸克喷注与胶子喷注通过各类τ轻子识别判别器的效率，与真实τ_h（tau_h）的通过效率的对比关系。上方两幅图采用W+喷注模拟样本中的喷注生成，下方两幅图则采用顶夸克对（tt）样本中的喷注生成。横向动量（pt）小于100 GeV的喷注与真实τ_h均纳入左侧两幅图的统计范畴，右侧两幅图则包含横向动量大于100 GeV的上述对象。判别器的工作点以实心圆点标注。富含夸克喷注的W+喷注事件样本中的喷注，通过判别器的效率高于tt事件样本中的喷注——后者的胶子喷注与b夸克喷注占比更高。在给定τ_h通过效率的前提下，横向动量小于100 GeV的喷注与τ_h对应的喷注效率，高于横向动量大于100 GeV的对应对象。与此前使用的多变量分析（MVA）判别器相比，DEEPTAU判别器在给定τ_h通过效率的情况下，始终将喷注效率降低1.8倍以上，且在τ_h高通过效率区间的降幅更为显著。高横向动量区间的额外性能提升，源于τ_h重建过程中纳入了更新后的衰变模式，此前使用的MVA判别器的曲线已体现这一结论：该曲线纳入了带有额外衰变模式的重建τ_h候选体。