"Figure 4b" of "Search for $CP$ violation in ttH and tH production in multilepton channels in proton-proton collisions at $\sqrt{s}$ = 13 TeV"

\Delta \eta_{B-B}, which is one of the input variables to the XGBoost used for CP discrimination in 3l + 0tau channel, defined in table 4.

Δη_{B-B}是用于3轻子+0τ道电荷共轭宇称（CP）鉴别的XGBoost模型的输入变量之一，其定义见表4。