大气臭氧层吸收有害的太阳紫外辐射，是人类必不可少的保护伞。然而人类大 量排放在大气中的氟利昂对臭氧层存在巨大的威胁，氟利昂在太阳紫外辐射下会发生解离， 解离产物氯会严重地破坏大气臭氧层。借助飞秒泵浦-探测技术在飞秒时间尺度上实时跟踪 氟利昂在紫外辐射下的解离过程，可深入认识其解离动力学机理。本项目结合飞秒泵浦-探 测技术和光电子影像及飞行时间质谱探测手段，通过测量氟利昂在紫外辐射下解离过程中不 同时刻的光电子影像和质谱，在飞秒时间尺度和分子空间尺度上实时探究氟利昂分子在紫外 辐射下的解离过程。用直观的影像和质谱信息实现对微观的解离反应过程的描述与追踪，获 得其详尽的解离动力学信息。深入认识氟利昂在紫外辐射下的解离动力学及其对解离光的依 赖关系，为进一步有效控制其对臭氧层破坏性的解离进程提供理论依据和实验基础。

Characters)：The ozone layer which absorbs harmful solar UV radiation is　an essential umbrella for human. However, a large number of exhausts of CFCs by human　in the atmosphere pose a great threat to the ozone layer. CFCs dissociate in the　solar UV radiation with the product of chlorine, which seriously damage the　atmospheric ozone layer. By femtosecond pump-probe techenique, real-time tracking　the dissociation of CFCs in the UV radiation on femtosecond time scale can derive　more and detailed dissociation dynamics. This project combined femtosecond　pump-probe technique and detection means of photoelectron imaging coupled with time　of flight mass spectrum. The dissociation dynamics of CFCs in the UV radiation will　be investigated in real time on femtosecond time scale and molecular spatial scale　by time-resolved photoelectron imaging and mass spectrum. The processes of dissociation reaction will be described and tracked by visual images and mass　spectra, and the further dissociation dynamics can be obtained. In-depth　understanding of dissociation dynamics of CFCs in the UV radiation and its dependence　on photolysis light can provide theoretical references and experimental basis for　further controling the dissociation processes with destruction to the ozone layer.