Vavilov–Cherenkov Radiation in the Region 200–300 nm in the Earth’s Atmosphere

Abstract

The results of the study of the radiation spectra of the Earth’s atmosphere in the ultraviolet (UV) and visible spectral regions are presented. The input window of the spectrometer was directed to the Sun or located at different angles to the axis through the solar disk center. The Vavilov–Cherenkov (VCh) radiation spectrum was recorded with a standard spectrometer in the region 200–300 nm for the first time. The threshold electron energy for VCh radiation excitation in air and the maximal angle of VCh radiation propagation with respect to the electron motion direction are calculated. The VCh radiation is assumed to be excited when high-energy solar wind particles are braking in the Earth’s atmosphere.