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Spectrum of the lightning stepped leader

1968; American Geophysical Union; Volume: 73; Issue: 22 Linguagem: Inglês

10.1029/jb073i022p06999

2156-2202

Richard E. Orville,

Atomic and Molecular Physics

Journal of Geophysical Research (1896-1977)Volume 73, Issue 22 p. 6999-7008 Spectrum of the lightning stepped leader Richard E. Orville, Richard E. OrvilleSearch for more papers by this author Richard E. Orville, Richard E. OrvilleSearch for more papers by this author First published: 15 November 1968 https://doi.org/10.1029/JB073i022p06999Citations: 62AboutPDF ToolsRequest permissionExport citationAdd to favoritesTrack citation ShareShare Give accessShare full text accessShare full-text accessPlease review our Terms and Conditions of Use and check box below to share full-text version of article.I have read and accept the Wiley Online Library Terms and Conditions of UseShareable LinkUse the link below to share a full-text version of this article with your friends and colleagues. Learn more.Copy URL Share a linkShare onEmailFacebookTwitterLinkedInRedditWechat Abstract A high-speed camera has been modified to a slitless spectrograph to record the spectral emissions from a section of the lightning channel. Spectral emissions from a 2-meter section of a negatively charged stepped-leader channel are recorded. The downward progression of the leader caused the isolated vertical section to radiate seven discrete times before the upward-moving return stroke produced an overexposed time-resolved spectrum. The discrete spectral emissions were recorded at intervals of 31–42 μsec. Stepped-leader spectral emissions in the 5600- to 6600-A regions are characterized by singly ionized nitrogen (N II) emissions at 5680 and 5942 A, and Hα emissions at 6563 A. These leader channel emissions vary as a function of time as the stepped leader progresses toward the ground. A temperature of 30,000°K is calculated for the leader step. 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Orville, The opacity of lightning, J. Geophys. Res., 7022, 5491–5497, 1965. Uman, M. A., R. E. Orville, L. E. Salanave, The density, pressure, and particle distribution in a lightning stroke near peak temperature, J. Atmospheric Sci., 213, 306–310, 1964. Citing Literature Volume73, Issue2215 November 1968Pages 6999-7008 ReferencesRelatedInformation