The demand for electron-impact cross sections has increased tremendously in recent years. There is, however, a special interest in such cross sections for hydrogen molecules and its isotopomers, HD and D 2 , because of their presence in tokamak edge plasmas, planetary atmospheres and at different astrophysical sites. This explains the need for having well validated sets of electron-impact cross sections for different processes. This work reviews the electron-scattering cross sections for elastic and inelastic processes at different electron energies for both these molecules. The elastic momentum transfer cross sections and inelastic cross sections for electron-impact rotational, vibrational and electronic excitation, emission, dissociation, ionization and dissociative electron attachment have been evaluated and well validated in this work wherever and whenever possible.

Electron capture processes by protons from hydrogenic ions in dense plasmas are investigated in accordance with a semiclassical version of the Bohr and Lindhard model using the straight-line trajectory method. The screened electron capture radius and screened bound state wave function are obtained by using the Debye–Hückel interaction potential. The scaled semiclassical electron capture probability is obtained as a function of the impact parameter, Debye length, and projectile velocity. The plasma screening effects on the target system is found to be quite small so that the plasma screening effects on the capture probability is mainly determined by the screened capture radius. The plasma screening effects on the scaled semiclassical capture probability for the intermediate energy projectile is more significant than those for the high-energy projectile. The maximum position of the capture probability approaches the target nucleus as the projectile energy increases.

Dynamic plasma screening effects on the electron capture process in kappa-Maxwellian plasmas are investigated using the semiclassical version of the Bohr-Lindhard model. The interaction potential and screened electron capture radius are obtained by considering the longitudinal component of the plasma dielectric function. The semiclassical electron capture probability is also obtained as a function of the impact parameter, Debye length, projectile velocity, and spectral index. It is found that the dynamic screening effects on the electron capture probability are more significant for low projectile energies. The maximum position of the scaled electron capture probability approaches the target nucleus with increasing projectile energy. The dynamic screening effect is also found to decrease with increasing spectral index.

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The quantum dynamic screening effects on the elastic electron-ion collisions are investigated in strongly coupled semiclassical plasmas. The second-order eikonal analysis with the impact parameter method is applied to obtain the eikonal phase shift and eikonal cross section as functions of the impact parameter, collision energy, thermal energy, de Broglie wavelength, and Debye length. The result shows that the magnitude of the eikonal phase shift decreases with increasing thermal energy. It is also found that the maximum position of the differential eikonal cross section is receded from the collision center with decreasing collision energy. It is also found that the total eikonal cross decreases with increasing de Broglie wavelength, especially for large collision energies. In addition, it is found that the thermal effect suppresses the total eikonal cross section.The elastic electron-ion collision process 1-3 in plasmas has received considerable attention, since this process is the one of the most important atomic processes and also has provided useful information on collision dynamics as well as various plasma parameters. It has been known that the screening interaction potential in weakly coupled classical plasmas would be characterized mostly by the standard Debye-Hückel model 4,5 since the average energy of interaction between plasma particles is smaller than the average kinetic energy of a plasma particle. However, it would be expected that the multiparticle correlation effects caused by simultaneous interactions of many particles should be taken into account to describe the interaction potential in dense strongly coupled plasmas. Recently, the interest in strongly coupled semiclassical plasmas has significantly increased due to the investigations on physical properties of astrophysical dense compact objects and also laser induced inertial confinement fusion plasmas. In these dense semiclassical plasmas, the interaction potential would not be properly described by the standard Debye-Hückel model because of quantum mechanical and strong collective effects of nonideal particle interactions. 6-10 Hence, it would be expected that the physical characteristics of collision in such dense plasmas differ radically from those in weakly coupled classical plasma. In addition, when the velocity of the plasma electron is comparable to or smaller than the velocity of the projectile electron, the conventional static screening model would not be quite reliable, since the projectile polarizes the surrounding plasma particles. Thus, in this paper, we investigate the quantum dynamic screening effects on the electronion collisions in strongly coupled semiclassical plasmas. The second-order eikonal analysis and effective dynamic interaction potential taking into account, the dynamic screening quantum mechanical effects are employed to obtain the eikonal phase shift and eikonal cross section as functions of the impact parameter, collision energy, thermal energy, de Broglie wavelength, and Debye length.For a given interaction pote...