HOT-ATOM REACTION YIELD AND ENERGY DISTRIBUTION

A general integral equation for the reaction probability of energetic ions slowing down in an arbitrary system is formulated. The equation is found to be equivalent to the Boltzmann equation for the energy distribution of incoming particles. An approximate solution corresponding to continuous slowing down is derived, expressing, e.g., the energy distribution through the flux distribution of incoming particles, the stopping power of the system, and the reaction cross sections. The approximate solution for the energy distribution is better the softer the potential, and is found to be accurate if stopping is dominated by target atoms with mass widely different from the mass of the incoming particles. In case of equal masses, the discrepancy is of the order of 50% for a nonreactive system and realistic interactions.