Accelerated He⁺ pickup ions (PUIs) downstream of quasiperpendicular shocks are studied as a function of the fast-mode Mach number (M_f) and shock obliquity (θ _Bn). We analyze 10 quasiperpendicular shocks with Mach numbers in the range [1, 7] observed by the Magnetospheric MultiScale (MMS) mission, and compare upstream and downstream He⁺ velocity distribution functions. For each shock event, we characterize the upstream PUI distribution and derive reduced 1D velocity distributions for the selected upstream and downstream intervals. We also compare the upstream-to-downstream ratio of spectral indices, computed from the He⁺ perpendicular distributions, to M_f and θ _Bn. We find a positive correlation of this spectral index ratio and M_f, which suggests that perpendicular energization of He⁺ PUIs is enhanced as the shock becomes stronger. These results inform modeling efforts of PUIs and shock-acceleration processes, particularly those taking place at the termination shock.

作为快速模式马赫数 (M _f ) 和激波倾角 ( θ _Bn )的函数，研究了准垂直激波下游的加速 He ⁺吸收离子 (PUI )。我们分析了磁层多尺度 (MMS) 任务观测到的马赫数范围 [1, 7] 内的 10 个准垂直激波，并比较了上游和下游 He ⁺速度分布函数。对于每个冲击事件，我们描述了上游 PUI 分布的特征，并为选定的上游和下游间隔推导出减少的一维速度分布。我们还将从 He ⁺垂直分布计算的光谱指数的上游与下游比率与 M _f和 θ _Bn。我们发现该光谱指数比与 M _f呈正相关，这表明 He ⁺ PUI 的垂直激励随着冲击的增强而增强。这些结果为 PUI 和冲击加速过程的建模工作提供了信息，特别是那些发生在终止冲击时的过程。