The processes of charge exchange and ionization in collisions of ground state hydrogen atom with fully stripped ions in a weakly coupled plasma are studied by the classical trajectory Monte Carlo method in the collision energy range 10-900 keV/ amu. The interparticle interactions are described by the Debye-Hückel model with inclusion of dynamical effects associated with the projectile velocity. The microcanonical distribution of initial state electronic coordinates and momenta has been determined by inclusion of plasma screening effects. The cross section dependencies on plasma parameters and ion charge and velocity are investigated. It is shown that plasma effects on charge exchange and ionization cross sections are significant and particularly pronounced at low collision velocities. The results of systematic cross section calculations for different values of Debye screening length ͑in the range 1 -50a 0 ͒ and ion charges ͑in the range 1-14͒ are presented.

Self-consistent calculations of the stopping power for alpha particles in hot dense Au plasmas are performed in a wide projectile energy range with a fixed density ρAu = 19.3 g cm−3 and the electron temperature range from 0.4 to 5 keV on the basis of the relativistic ion-sphere model. All the mechanisms, which have strong influences on stopping power, are discussed in detail. The distribution of the free electron velocity component is found to be much flatter than the Maxwellian distribution due to the strong electrostatic field within the ion sphere in the hot dense plasmas, which results in the suppression of the stopping mechanism by plasma polarization and close collision for a projectile energy below 1 MeV u−1. The influence of inelastic scattering is considerably weakened due to the strong neutralization from the impact excitation, ionization and their reverse processes almost in the entire energy range below 10 MeV u−1 although the contribution of each process is quite large. Nuclear stopping is found to increase with the temperature. Our calculations are compared with other models and some explanations are presented for the difference between our results and other models. The Bethe equation is found to overestimate the contribution of inelastic processes by at least 10%. Different mechanisms are found to play their role in different energy ranges and all the mechanisms should be considered in order to get reliable data of stopping power.

The experiments of displacement damage effects on CMOS APS image sensors induced by neutron irradiation from a nuclear reactor are presented. The CMOS APS image sensors are manufactured in the standard 0.35 μm CMOS technology. The flux of neutron beams was about 1.33 × 108 n/cm2s. The three samples were exposed by 1 MeV neutron equivalent-fluence of 1 × 1011, 5 × 1011, and 1 × 1012 n/cm2, respectively. The mean dark signal (KD), dark signal spike, dark signal non-uniformity (DSNU), noise (VN), saturation output signal voltage (VS), and dynamic range (DR) versus neutron fluence are investigated. The degradation mechanisms of CMOS APS image sensors are analyzed. The mean dark signal increase due to neutron displacement damage appears to be proportional to displacement damage dose. The dark images from CMOS APS image sensors irradiated by neutrons are presented to investigate the generation of dark signal spike.

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With the effects of the projectile recoil and plasma polarization considered, the slowing down of 3.54 MeV alpha particles is studied in inertial confinement fusion DT plasmas within the plasma density range from 1024 to 1026 cm−3 and the temperature range from 100 eV to 200 keV. It includes the rate of the energy change and range of the projectile, and the partition fraction of its energy deposition to the deuteron and triton. The comparison with other models is made and the reason for their difference is explored. It is found that the plasmas will not be heated by the alpha particle in its slowing down the process once the projectile energy becomes close to or less than the temperature of the electron or the deuteron and triton in the plasmas. This leads to less energy deposition to the deuteron and triton than that if the recoil of the projectile is neglected when the temperature is close to or higher than 100 keV. Our model is found to be able to provide relevant, reliable data in the large range of the density and temperature mentioned above, even if the density is around 1026 cm−3 while the deuteron and triton temperature is below 500 eV. Meanwhile, the two important models [Phys. Rev. 126, 1 (1962) and Phys. Rev. E 86, 016406 (2012)] are found not to work in this case. Some unreliable data are found in the last model, which include the range of alpha particles and the electron-ion energy partition fraction when the electron is much hotter than the deuteron and triton in the plasmas.

Charge transfer processes due to collisions of ground state Si 3+ ͑3s 1 S͒ ions with atomic hydrogen are investigated using the quantum-mechanical molecular-orbital close-coupling ͑MOCC͒ and classical-trajectory Monte Carlo ͑CTMC͒ methods. The MOCC calculations utilize ab initio adiabatic potentials and nonadiabatic radial coupling matrix elements obtained from Herrero et al. ͓J. Phys. B 29, 5583 ͑1996͔͒ which were calculated with a full configuration-interaction method. Total and state-selective single-electron capture cross sections are obtained for collision energies from 0.01 eV/ u to 1 MeV/ u. Total and state-selective rate coefficients are also presented for temperatures from 2 ϫ 10 3 K to 10 7 K. Comparison with existing data reveals that the total CTMC cross sections are in good agreement with the experimental measurements at the higher considered energies and that previous Landau-Zener calculations underestimate the total rate coefficients by a factor of up to two. The CTMC calculations of target ionization are presented for high energies.

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