Abstract
The intensities of muon and electron neutrinos at ground level have been calculated for vertical and horizontal directions and the muon-neutrino spectrum has been found for intermediate angles. The calculations have been made for what is regarded as the most likely model of the propagation of the components of the cosmic radiation through the atmosphere, and the dispersion in the neutrino spectrum arising from uncertainties in the model has been examined.
The intensity of muon neutrinos is found to be greater in the horizontal than in the vertical direction, the ratio increasing with energy from 1.43 at 1 GeV through 2.12 at 10 GeV to 3.70 at 1000 GeV.
The uncertainty in the horizontal intensity of muon neutrinos is less than that in the vertical direction, typical values being+8-11% at 10 GeV and 12-16% at 100 GeV in the horizontal direction and +17-22% at 10 GeV and +33-43% at 100 GeV in the vertical direction.