Daytime observation technique for Fe Boltzmann Lidar
Wang Wei, Cheng Xuewu, Huang Wentao, Li Xianxin, Fang Shuo, Yang Guotao, Ban Chao, Wang Rui, Wang Zhangjun, Xiao Chunlei, Du Lifang, Wang Shuwen, Ji Kaijie, Xu Sihan, Yang Yong, Lin Xin, Liu Linmei, Pan Weilin, Li FaquanIn this paper, a Fe Boltzmann temperature-measuring lidar featuring narrow-linewidth solid-state lasers and daytime detection capability is presented. The system adopts seed-injected optical parametric oscillator and amplifier technology, effectively compressing the laser linewidth to below 200 MHz. Moreover, a frequency stabilization scheme based on potassium saturated absorption spectroscopy locks the laser wavelength to the center of the iron resonance lines. In addition, the system is equipped with dual-wavelength etalons at 372 nm and 374 nm, with filter bandwidths of 8.3 GHz and 9.8 GHz, respectively. Together with high-precision coordinated temperature–pressure control and a large-aperture receiving telescope, the system effectively suppresses intense daytime background light and enables daytime observations. The demonstrated daytime-capable Fe lidar provides an effective scheme for precise probing of atmospheric dynamics in the mesosphere and lower thermosphere.