太阳风质子注入与氢扩散：与M3观测的模型比较
Solar Wind Proton Implantation and Hydrogen Diffusion: Model Comparisons to M3 Observations
AI总结：
研究月球表面3微米吸收特征，通过太阳风质子注入、氢扩散等模型与M3观测比较，采用加权激活能仓表示法计算表面丰度，拟合出相关参数，再现了主要丰度结构，揭示了模型与数据在部分区域的差异。
AI中文摘要：
月球矿物绘图仪（M3）在月球表面观测到广泛的3微米吸收特征，通常归因于表面的OH和/或H2O。该特征随纬度、地方时和月相变化，表明至少部分光学活性储层是动态的。我们将M3丰度估计与全球太阳风质子注入、氢扩散和H2外逸层模型进行比较。模型跟踪注入的H在颗粒上边缘的情况、热激活的保留和损失、重组H2释放以及与太阳风、磁鞘和磁尾相关的相驱动源变化。我们使用加权激活能仓表示法计算表面丰度，减少了低通量区域的粒子采样噪声。高斯有效激活能分布的精细网格表明，低纬度和中纬度M3趋势与Ec = 0.520 eV附近、Ew = 0.090 eV宽度的分布最匹配。该模型再现了主要的地方时和相位相关丰度结构，模型与数据在等离子体过渡区间和高纬度行为的差异可能反映了额外的采样、饱和或表面等离子体过程。
英文摘要：
The Moon Mineralogy Mapper (M3) observed a widespread 3-micron absorption feature on the lunar surface, commonly attributed to surficial OH and/or H2O. The feature varies with latitude, local time, and lunar phase, suggesting that at least part of the optically active reservoir is dynamic. We compare phase- and local-time-resolved M3 abundance estimates with a global solar wind proton implantation, hydrogen diffusion, and H2 exosphere model. The model tracks implanted H in the upper grain rim, thermally activated retention and loss, recombinative H2 release, and phase-driven source variations associated with the solar wind, magnetosheath, and magnetotail. We compute the surface abundance using a weighted activation-energy-bin representation, in which the activation-energy distribution is discretized into fixed probability-weighted bins rather than sampled stochastically by Monte Carlo particles. This implementation reduces particle sampling noise in low-flux regions. A refined grid of Gaussian effective activation-energy distributions shows that the low- and mid-latitude M3 trends are best matched by distributions centered near Ec = 0.520 eV with width Ew = 0.090 eV. The preferred case gives a combined low- and mid-latitude RMSE of approximately 27 ppm and a small mean bias of only a few ppm. These fitted parameters should be interpreted as an effective response of the M3-sensitive retained H/OH reservoir, not as a unique mineralogical activation energy. The model reproduces the dominant local-time and phase-dependent abundance structure, including the reduced retained abundance near local noon, while model-data differences near plasma-transition intervals and high-latitude behavior may reflect additional sampling, saturation, or surface-plasma processes.
