Development of an Excimer Laser-Based Lidar System for Tropospheric Ozone Concentration Measurements

摘要

A ground based Raman Lidar is being developed for daytime and nighttime ozone monitoring in the lower troposphere (0.2- 2 km). The system unitizes a 30" Cassegrain telescope and a KrF excimer laser transmitter operating at 248 nm and up to 20 W average power. Both analog and photon-counting detection methods are designed to produce measurements. The physics governing the system is based on Raman scattering of the laser photons by N_2 at 263 nm and O_2 at 258 nm and the attenuation of the laser and Raman back-scattered photons by ozone absorption. Here, we present results from a model based on the described system. To obtain the ozone concentration, we calculate the single and double ratio of the Raman Scattered signals throughout the range. The model simulations indicate that the measurements are feasible with proper care given to counting statistics.