On Cherenkov radiation from a shower

Cherenkov radiation from a shower is discussed in terms of the angle-energy distribution of emitted photons. The Cherenkov radiation spectrum is estimated assuming that the shower has Gaussian shape. The contribution of coherent and non-coherent parts of Cherenkov radiation and the broadening of the angle distribution are discussed in terms of the ratio of the shower shape parameters to the radiation wave length. The model shows a satisfactory agreement with experimental data.