Energy deposition by precipitating keV range protons and neutral hydrogen atoms into the equatorial atmosphere: dependence on the neutral atmosphere model

The problem of the precipitation of keV range protons and neutral hydrogen atoms into the equatorial atmosphere is studied by the Monte-Carlo technique, and the energy deposition is calculated for different atmospheric models corresponding to low, medium and high solar activity conditions. It is found that the total energy deposited is independent of the atmospheric model and is equal to 16% of the incident energy, but the energy deposition profile varies. The dependence of the profile parameters on the neutral atmospheric model is examined in detail. An empirical model of the Chapman type distribution, involving only the neutral atmospheric density, has been developed to represent the energy deposition profile for any solar activity condition.