Electron density measurement of a lightning stepped leader by oxygen spectral lines
Jianyong Cen,
Qiang Hou,
Ping Yuan,
Jinjun Zhang,
Minna Sun,
Junxing Pan,
Zengli Cao
Affiliations
Jianyong Cen
College of Physics and Information Engineering, Shanxi Normal University, Linfen, Shanxi 041000, China
Qiang Hou
College of Physics and Information Engineering, Shanxi Normal University, Linfen, Shanxi 041000, China
Ping Yuan
Key Laboratory of Atomic and Molecular Physics and Functional Materials of Gansu Province, College of Physics and Electronic Engineering, Northwest Normal University, Lanzhou, Gansu 730070, China
Jinjun Zhang
College of Physics and Information Engineering, Shanxi Normal University, Linfen, Shanxi 041000, China
Minna Sun
College of Physics and Information Engineering, Shanxi Normal University, Linfen, Shanxi 041000, China
Junxing Pan
College of Physics and Information Engineering, Shanxi Normal University, Linfen, Shanxi 041000, China
Zengli Cao
College of Physics and Information Engineering, Shanxi Normal University, Linfen, Shanxi 041000, China
The time-resolved spectrum of a lightning stepped leader in downward process has been obtained by using a slitless spectrograph. Neutral oxygen and nitrogen spectral lines in the near infrared region are observed in the spectra. The electron density of the lightning stepped leader was calculated by using the Stark broadening of the oxygen spectral lines at 777.4 and 844.6 nm. The evolution characteristic of the electron density with time and channel height of the lightning stepped leader was analysed. The results shown that the electron density of the lightning stepped leader was in the order of 1018 cm-3. The electron density decreased when the lightning stepped leader propagates downward to ground.
