COSMIC-RAY IONIZATION OF LOWER VENUS ATMOSPHERE

Cosmic ray particles passing through dense lower atmosphere of Venus d ecay giving rise to various charged and neutral particles. The flux an d degradation of dominant cascade particles namely neutrinos and pions are computed and ionization contributions at lower altitudes are esti mated. Using the height profile of pion flux, the muon flux is compute d and used to estimate ionization at lower altitudes. It is shown that cosmic ray produced ionization descends to much lower altitudes inter cepting the thickness of Venus cloud deck. The dynamical features of V enus cloud deck are used to allow the likely charging and charge separ ation processes resulting into cloud-to-cloud lightning discharges.