Universality of electron-positron distributions in extensive air showers

p a Using a large set of simulated extensive air showers, we investigate universality features of electron and positron distributions in very-highenergy cosmic-ray air showers. Most particle distributions depend only on the depth of the shower maximum and the number of particles in • the cascade at this depth. We provide multi-dimensional parameterizations for the electron-positron distributions in terms of particle energy, vertical and horizontal momentum angle, lateral distance, and time distribution of the shower front. These parameterizations can be used to ' ^ obtain realistic electron-positron distributions in extensive air showers for data analysis and simulations of Cherenkov radiation, fluorescence 0 signal, and radio emission. £ CO cd