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３巻１号 （2022年4月） Volume 3, Number 1 (April 2022) |
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解説: 狭帯域レーザを用いたナトリウムライダーによる中間圏界面の温度・風速計測 pp. 36-45 Technical Review: Mesopause temperature and wind observations by a narrowband Na lidar 川原 琢也，野澤 悟徳，斎藤 徳人， 津田 卓雄，川端 哲也，和田 智之 Takuya D. Kawahara, Satonori Nozawa, Norihito Saito, Takuo T. Tsuda, Tetsuya Kawabata and Satoshi Wada |
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Abstract Metallic atoms, such as Na, K, Li, Ca, Fe, etc., originating from meteors are concentrated and forms metal layers in the mesopause region(80‒115 km)in the Earthʼs upper atmosphere. This paper details Na lidar observation techniques to measure temperature and line-of-sight wind velocity in the Na layer. The technique needs a narrowband 589 nm laser and a measurement of a fine structure Doppler-free spectrum of the NaD2 lines. Based on the robust and reliable measurement techniques established by a Colorado State University group, an Nd:YAG-based Na lidar was deployed at EISCAT(European Inco- herent Scatter)radar site(69.6°N, 19.2°E)in Norway in 2010. Utilizing the advantages of the high power(4 W)laser output, five-direction observations are performed to measure spatial distribution of temperature and wind velocity. |