The wavelength dependence and temporal evolution of the hypervelocity impact self‐luminous plume (or “flash”) from CO₂ ice, water ice, and frozen Martian and lunar regolith simulant targets have been investigated using the Kent two‐stage light‐gas gun. An array of 10 band‐pass filtered photodiodes and a digital camera monitored changes in the impact flash intensity during the different phases of the emitting ejecta. Early‐time emission spectra were also recorded to examine short‐lived chemical species within the ejecta. Analyses of the impact flash from the varied frozen targets show considerable differences in temporal behavior, with a strong wavelength dependence observed within monitored near‐UV to near‐IR spectral regions. Emission spectra showed molecular bands across the full spectral range observed, primarily due to AlO from the projectile, and with little or no contribution from vaporized metal oxides originating from frozen regolith simulant targets. Additional features within the impact flash decay profiles and emission spectra indicate an inhomogeneity in the impact ejecta composition. A strong correlation between the density of water ice‐containing targets and the impact flash rate of decay was shown for profiles uninfluenced by significant atomic/molecular emission, although the applicability to other target materials is currently unknown. Changes in impact speed resulted in considerable differences in the temporal evolution of the impact flash, with additional variations observed between recorded spectral regions. A strong correlation between the impact speed and the emission decay rate was also shown for CO₂ ice targets. These results may have important implications for future analyses of impact flashes both on the lunar/Martian surface and on other frozen bodies within the solar system.

中文翻译：

---

二氧化碳冰，水冰以及冻结的火星和月球重石模拟目标的冲击闪蒸演变

超高速的波长依赖性和时间演变会影响来自CO _2的自发光羽流（或“闪光”）使用肯特两级轻气炮对冰，水冰以及冻结的火星和月球重石模拟目标进行了研究。一组10个带通滤波的光电二极管和一台数码相机监视发射射流不同阶段中冲击闪光强度的变化。还记录了早期发射光谱，以检查喷射器内的短寿命化学物种。对来自各种冻结目标的冲击闪光的分析显示，时间行为存在相当大的差异，在受监测的近紫外至近红外光谱区域内观察到强烈的波长依赖性。发射光谱显示出观察到的整个光谱范围内的分子带，这主要归因于来自弹丸的AlO，而来自冷冻重结晶模拟目标的汽化金属氧化物几乎没有贡献。冲击闪光衰减曲线和发射光谱内的其他特征表明冲击喷射成分中的不均匀性。对于不受显着原子/分子发射影响的剖面，水冰含靶的密度与冲击闪速衰减之间显示出很强的相关性，尽管目前尚不适用于其他靶材料。撞击速度的变化导致撞击闪光的时间演变有相当大的差异，在记录的光谱区域之间观察到其他变化。二氧化碳的撞击速度和排放衰减率之间也显示出很强的相关性 对于不受显着原子/分子发射影响的剖面，水冰含靶的密度与冲击闪速衰减之间显示出很强的相关性，尽管目前尚不适用于其他靶材料。撞击速度的变化导致撞击闪光的时间演变有相当大的差异，在记录的光谱区域之间观察到其他变化。二氧化碳的撞击速度和排放衰减率之间也显示出很强的相关性 对于不受显着原子/分子发射影响的剖面，水冰含靶的密度与冲击闪速衰减之间显示出很强的相关性，尽管目前尚不适用于其他靶材料。撞击速度的变化导致撞击闪光的时间演变有相当大的差异，在记录的光谱区域之间观察到其他变化。二氧化碳的撞击速度和排放衰减率之间也显示出很强的相关性 在记录的光谱区域之间观察到其他变化。二氧化碳的撞击速度和排放衰减率之间也显示出很强的相关性 在记录的光谱区域之间观察到其他变化。二氧化碳的撞击速度和排放衰减率之间也显示出很强的相关性_2个冰目标。这些结果可能对月球/火星表面以及太阳系内其他冰冻物体上的撞击闪光的未来分析具有重要意义。