EAGER: Thermospheric High Power Rayleigh Lidar

研究人员将开发一种瑞利激光雷达仪器，该仪器将采用一种新的高功率二极管泵浦YAG激光器。 传统的瑞利激光雷达使用8-10瓦脉冲激光器和1米级望远镜，可以达到70公里的高度，积分时间相对较短。 超过80公里，需要1小时的积分时间。 近年来，脉冲YAG激光器已被开发用于商业目的，具有100-1000 W的平均功率和8 kHz的脉冲重复频率。 将研制的高功率激光雷达将能够在125公里的高度进行测量，积分时间为1小时或更短。工程涉及将8 kHz（高频）激光脉冲分成8个1 kHz的轻微分离光束，用于150公里的时间选通返回。 多个光束被成像到高量子效率的EMCCD成像器，其中行时钟用于时间范围信息。 整个系统采用了新的但现有的技术，低成本，高可靠性的操作，理想的远程设施仪表。 仪器开发人员将在新墨西哥州的马格达莱纳岭天文台运行两个晚上来测试仪器，该天文台有一个直径为2.4米的镜子。 研究表明，在100至140公里高度之间，中性大气的动态变化极大。 本科生和研究生将参与开发，以帮助培养下一代参与高层大气研究的工程师和科学家。

The investigators will develop a Rayleigh lidar instrument incorporating a new, high-power, diode-pumped YAG laser. The traditional Rayleigh lidars, which use 8-10 Watt pulsed lasers and 1-meter class telescopes, reach altitudes of 70 km with relatively short integration times. Above 80 km, one-hour integration times are required. In recent years, pulsed YAG lasers have been developed for commercial purposes with 100-1000 W average powers and 8 kHz pulse repetition frequencies. The high power lidar to be developed will be able to make measurements up to 125 km altitude with integration times of one hour or less. The engineering involves splitting 8 kHz (high frequency) laser pulses into eight 1 kHz slightly separated beams for time gated returns to 150 km. The multiple beams are imaged to a high-quantum-efficiency, EMCCD imager, where row clocking is employed for time range information. The entire system incorporates new but existing technology, for low cost, highly reliable operations, ideal for remote facility instrumentation. The instrument developers will test the instrument by operating it for two nights at the Magdalena Ridge Observatory in New Mexico, which has a 2.4 m diameter mirror. Studies have shown extreme variability in the dynamics of the neutral atmosphere between 100 and 140 km altitude. Undergraduate and graduate students will be involved with the development to help train the next generation of engineers and scientists involved in upper atmospheric studies.