Effects of atmospheric attenuation on lightning spectrum

<p>Spectrum carries important information reflecting atomic and molecular processes inside light source. Accurate spectral diagnosis is of vital significance in revealing microscopic physical mechanism of lightning discharge process. Aimed at the problems of atmospheric&nbsp;attenuation in long-distance lightning spectrum observations,&nbsp;considering the influence of atmospheric attenuation, grating efficiency and camera response on the observed spectrum, the spectral correction is&nbsp;carried out in this work.&nbsp;Based on the restored spectrum, the&nbsp;temperature of&nbsp;core current-carrying channel&nbsp;and the mean temperature of the luminous channel were calculated respectively. The result showed that the temperature of&nbsp;core current-carrying&nbsp;channel&nbsp;at initial stage of return stroke could reach up to 40000-45000 K, which was about 15000 K higher than the value directly obtained from observed spectrum. In addition, there is a steep&nbsp;temperature gradient between the core current-carrying channel and its peripheral luminous channel.&nbsp;This work can provide more precise parameters for further&nbsp;quantitative investigation on physical characteristic of lightning channel, and it also has application&nbsp;value&nbsp;for improving the&nbsp;spectral diagnostic techniques on celestial body&nbsp;and other natural luminous process.</p>