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The plane-wave Born approximation with Coulomb, relativistic, and exchange corrections is employed to obtain the K-, L1-, L2-, L3-, and M-shell ionization cross sections of a number of atoms bombarded by electrons and positrons in the energy range varying from the threshold of ionization to 1 GeV. Transverse interaction of virtual photons with atoms is also included and it is found to be of great significance for impact energies greater than about 1 MeV. For K- and L-shell ionization, good agreement between the theoretical values and various experimental data for electron-impact cross sections is obtained. However, for the M shell, the theory overestimates the experimental cross sections. For positron impact the agreement between the present results and the limited experimental data is found to be quite satisfactory.

Abstract. Electron-impact v i → v f vibrational excitations cross sections, involving rovibrationally excited N 2 (v i , J) and NO(v i , J) molecules (fixed J), are calculated for collisions occurring through the nitrogen resonant electronic state N − 2 (X 2 Π g ), and the three resonant states of nitric oxide NO − ( 3 Σ − , 1 ∆, 1 Σ + ). Complete sets of cross sections have been obtained for all possible transitions involving 68 vibrational levels of N 2 (X 1 Σ + g ) and 55 levels of NO(X 2 Π), for the incident electron energy between 0.1 and 10 eV. In order to study the rotational motion in the resonant processes, cross sections have been also computed for rotationally elastic transitions characterized by the rotational quantum number J running from 0 through 150. The calculations are performed within the framework of the local complex potential model, by using potentials energies and widths optimized in order to reproduce the experimental cross sections available in literature. Rate coefficients are calculated for all the (v i , J) → (v f , J) transitions by assuming a Maxwellian electron energy distribution function in the temperature range from 0.1 eV to 100 eV.All the produced numerical data can be accessed at

The modeling of atmospheric gas, interacting with the space vehicles in re-entry conditions in planetary exploration missions, requires large set of scattering data for all those elementary processes occurring in the system. A fundamental aspect of re-entry problems is represented by the strong nonequilibrium conditions met in the atmospheric plasma close to the surface of the thermal shield, where numerous interconnected relaxation processes determine the evolution of the gaseous system towards the equilibrium conditions. A central role is played by the vibrational exchanges of energy, so that collisional processes involving vibrationally excited molecules assume a particular importance. In the present paper, theoretical calculations of complete sets of vibrationally state-resolved cross sections and rate coefficients are reviewed, focusing on the relevant classes of collisional processes: resonant and non-resonant electronimpact excitation of molecules, atom-diatom and molecule-molecule collisions as well as gas-surface interaction. In particular, collisional processes involving atomic and molecular species, relevant to Earth (N 2 ,O 2 ,NO), Mars (CO 2 ,CO,N 2) and Jupiter (H 2 ,He) atmospheres are considered.