Laboratory Measurements of Superthermal H- and O- Atom Collisions Relevant to the Upper Atmosphere

与高层大气相关的超热氢原子和氧原子碰撞的实验室测量

• 批准号: 9811420
• 负责人: Ara Chutjian
• 金额: $ 24万
• 依托单位: California Institute of Technology
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 1999
• 资助国家: 美国
• 起止时间: 1999-06-01 至 2003-05-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=9811420&HistoricalAwards=false
• 关键词: Laboratory; Measurements; Superthermal; Atom; Collisions

Fast hydrogen, nitrogen, and oxygen atoms in the energy range 1-100 eV and higher are produced in the earth's upper atmosphere through a variety of processes. Such fast ground-state hydrogen (Hf) and oxygen (Of) atoms will be generated in the laboratory energy range 2-100 eV using a unique experimental facility at JPL. The fast atoms will then be used to study two classes of atmospheric reactions with the important species N2, O2, and NO. These reaction classes are (a) electron-capture and stripping, where cross-section and mass-charge ration measurements are made using a Penning ion trap, and (b) infrared (vibrational) excitation and emission, where cross sections are measured using an integrating sphere coupled to a Fourier-transform infrared spectrometer.The work proposed herein represents a unique combination of facilities and capital items. The fast-atom source generates the fast ground-state Hf and Of atoms by forming their respective negative ions, accelerating to the desired final energy, and laser-detaching the electron to leave a fast neutral species in its ground atomic state. The facility was developed under Air Force funding, the Penning trap for use in (a) was developed under NASA funding, and the FTIR spectrometer to be used in (b) was purchased under Air Force funding. The facility is the only one of its kind capable of generating the ground-state atoms and making measurements in this difficult 2-100 eV neutral energy range.

能量范围在1-100 eV及更高的快速氢、氮和氧原子通过各种过程在地球的高层大气中产生。 这种快速基态氢（Hf）和氧（Of）原子将使用JPL的独特实验设施在实验室能量范围2-100 eV内产生。 然后，快速原子将用于研究两类与重要物种N2、O2和NO的大气反应。这些反应类别是（a）电子捕获和剥离，其中使用Penning离子阱进行截面和质荷比测量，以及（B）红外（振动）激发和发射，其中使用耦合到傅立叶变换器的积分球测量横截面，本文提出的工作代表了设施和资本项目的独特组合。 快原子源通过形成它们各自的负离子、加速到期望的最终能量、以及激光分离电子以留下处于其基态原子态的快中性物质来生成快基态Hf和Of原子。 该设施是在空军的资助下开发的，用于（a）的潘宁阱是在NASA的资助下开发的，用于（B）的FTIR光谱仪是在空军的资助下购买的。 该设施是唯一一个能够产生基态原子并在这个困难的2-100 eV中性能量范围内进行测量的设施。