Laboratory Measurements of Fast Hydrogen (H) and Oxygen (O) Atom Collisions Relevant to the Upper Atmosphere

能量范围在1-100 eV和更高的快速氢、氮和氧原子在地球的高层大气中通过诸如光解离、辐射复合、解离复合、解离附着、电荷交换和超弹性（淬火）碰撞等现象产生。这些现象中有许多是由闪电放电引起的，闪电放电是造成精灵、红色精灵和蓝色喷流的原因。快速原子与N2、O2、NO、H2O、CO2等物质碰撞，通过化学反应或直接激发靶，在高层大气和热层中产生辐射，如氢夜极光和极尖极光，以及热氧日冕和地日冕。利用喷气推进实验室的一个独特的实验设施，在NSF的支持下建造，将在实验室能量范围2-100 eV内产生快速基态氢原子和氧原子。快速原子将被用来研究两类大气反应的重要物种N2，O2和NO。这些类是（a）红外（振动）激发和发射，其中截面测量使用积分球耦合到碲镉汞红外探测器;和（B）电子捕获和剥离，其中截面和质量/电荷比测量使用潘宁离子阱。

Fast hydrogen, nitrogen, and oxygen atoms in the energy range 1-100 eV and higher are produced in the earth's upper atmosphere through phenomena such as photodissociation, radiative recombination, dissociative recombination, dissociative attachment, charge exchange, and superelastic (quenching) collisions. Many of these phenomena are induced by lightning discharges, which are responsible for emissions known as elves, red sprites, and blue jets. The fast atoms collide with species such as N2, O2, NO, H2O, CO2, etc. to produce, either through chemical reaction or direct excitation of the target, emissions in the upper atmosphere and thermosphere such as the hydrogen nighttime and polar-cusp aurora, and the hot oxygen corona and geocorona. Using a unique experimental facility at JPL, constructed with prior NSF support, fast ground-state hydrogen and oxygen atoms will be generated in the laboratory energy range 2-100 eV. The fast atoms will be used to study two classes of atmospheric reactions with the important species N2, O2, and NO. These classes are (a) infrared (vibrational) excitation and emission, where cross sections are measured using an integrating sphere coupled to a HgCdTe infrared detector; and (b) electron-capture and stripping, where cross-section and mass/charge ratio measurements are made using a Penning ion trap.