Atomic Particle

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S A Yakovleva - One of the best experts on this subject based on the ideXlab platform.

  • estimating inelastic heavy Particle hydrogen collision data ii simplified model for ionic collisions and application to barium hydrogen ionic collisions
    Astronomy and Astrophysics, 2017
    Co-Authors: A K Belyaev, S A Yakovleva
    Abstract:

    Aims. A simplified model is derived for estimating rate coefficients for inelastic processes in low-energy collisions of heavy Particles with hydrogen, in particular, the rate coefficients with high and moderate values. Such processes are important for non-local thermodynamic equilibrium modeling of cool stellar atmospheres. Methods. The derived method is based on the asymptotic approach for electronic structure calculations and the Landau-Zener model for nonadiabatic transition probability determination. Results. It is found that the rate coefficients are expressed via statistical probabilities and reduced rate coefficients. It is shown that the reduced rate coefficients for neutralization and ion-pair formation processes depend on single electronic bound energies of an Atomic Particle, while the reduced rate coefficients for excitation and de-excitation processes depend on two electronic bound energies. The reduced rate coefficients are calculated and tabulated as functions of electronic bound energies. The derived model is applied to barium-hydrogen ionic collisions. For the first time, rate coefficients are evaluated for inelastic processes in Ba + + H and Ba 2+ + H − collisions for all transitions between the states from the ground and up to and including the ionic state.

A K Belyaev - One of the best experts on this subject based on the ideXlab platform.

  • estimating inelastic heavy Particle hydrogen collision data ii simplified model for ionic collisions and application to barium hydrogen ionic collisions
    Astronomy and Astrophysics, 2017
    Co-Authors: A K Belyaev, S A Yakovleva
    Abstract:

    Aims. A simplified model is derived for estimating rate coefficients for inelastic processes in low-energy collisions of heavy Particles with hydrogen, in particular, the rate coefficients with high and moderate values. Such processes are important for non-local thermodynamic equilibrium modeling of cool stellar atmospheres. Methods. The derived method is based on the asymptotic approach for electronic structure calculations and the Landau-Zener model for nonadiabatic transition probability determination. Results. It is found that the rate coefficients are expressed via statistical probabilities and reduced rate coefficients. It is shown that the reduced rate coefficients for neutralization and ion-pair formation processes depend on single electronic bound energies of an Atomic Particle, while the reduced rate coefficients for excitation and de-excitation processes depend on two electronic bound energies. The reduced rate coefficients are calculated and tabulated as functions of electronic bound energies. The derived model is applied to barium-hydrogen ionic collisions. For the first time, rate coefficients are evaluated for inelastic processes in Ba + + H and Ba 2+ + H − collisions for all transitions between the states from the ground and up to and including the ionic state.

E. K. Gol - One of the best experts on this subject based on the ideXlab platform.

  • Quasihard-Sphere Model in Simulation of the Processes of Particle Scattering
    2000
    Co-Authors: V. A. Vol, E. K. Gol
    Abstract:

    A model of interAtomic potentials of interaction is suggested for static simulation of the processes of elastic scattering of Atomic Particles by atoms of gas, plasma, and solid. In the developed model, the Atomic Particle radii, whose magnitude depends on the energy of their relative motion, are internal parameters. The sug- gested quasihard-sphere model enables one to simulate elastic processes of scattering of Atomic Particles, using different interAtomic potentials of interaction with relatively high rates of statistical simulation characteristic of simulation within the hard-sphere model. The Born-Mayer potential is selected as the interAtomic potential of interaction and modified for a wide class of partners in Atomic collisions. It is demonstrated that the suggested mathematical model of quasihard spheres describes fairly correctly the processes of elastic scattering of atoms in a gas medium and of displaced atoms in a solid with an almost constant rate of static simulation. © 2000 MAIK "Nauka/Interperiodica".

E. K. Gol’man - One of the best experts on this subject based on the ideXlab platform.

  • Quasihard-sphere model in simulation of the processes of Particle scattering
    Technical Physics, 2000
    Co-Authors: V. A. Vol’pyas, E. K. Gol’man
    Abstract:

    A model of interAtomic potentials of interaction is suggested for static simulation of the processes of elastic scattering of Atomic Particles by atoms of gas, plasma, and solid. In the developed model, the Atomic Particle radii, whose magnitude depends on the energy of their relative motion, are internal parameters. The suggested quasihard-sphere model enables one to simulate elastic processes of scattering of Atomic Particles, using different interAtomic potentials of interaction with relatively high rates of statistical simulation characteristic of simulation within the hard-sphere model. The Born-Mayer potential is selected as the interAtomic potential of interaction and modified for a wide class of partners in Atomic collisions. It is demonstrated that the suggested mathematical model of quasihard spheres describes fairly correctly the processes of elastic scattering of atoms in a gas medium and of displaced atoms in a solid with an almost constant rate of static simulation.

I.f. Urazgil'din - One of the best experts on this subject based on the ideXlab platform.

  • The effect of a band edge of surface electronic states on charge exchange in atom-surface collisions
    Surface Science, 1997
    Co-Authors: M.yu. Gusev, D.v. Klushin, Sergey V. Sharov, I.f. Urazgil'din
    Abstract:

    Within the framework of a time-dependent Anderson-Newns model, charge exchange between an Atomic Particle and a surface with a finite band of electronic states is considered. Asymptotically exact solutions of the model for different time dependences of hopping matrix elements between the Atomic and band states are derived. It is shown that for a finite energy band, the resulting charge state of the Atomic Particle can be a non-monotonic function of its energy only when the time dependence of the coupling has an adiabatically part.

  • Charge state of Atomic Particles ejected from solid surfaces: influence of initial conditions
    Nuclear Instruments and Methods in Physics Research Section B: Beam Interactions with Materials and Atoms, 1994
    Co-Authors: D.v. Klushin, Maxim Gusev, I.f. Urazgil'din
    Abstract:

    Abstract The charge exchange between the solid and the Atomic Particle during its ejection from the surface was considered in the framework of the time-dependent Anderson-Newns model. Use of equilibrium initial conditions (in the sense of the summary system of a “hybridized atom-surface”) is justified. An analytical solution for the final charge state of the Atomic Particle was derived. Two channels of charge exchange were shown to be present: the “dynamical” one (due to the finiteness of the characteristic time of hybridization switching off) and that related to the system “memory” (influence of the initial state). Situations in which one of the mentioned channels predominated were considered, as well as the case of the quantum interference of these channels leading to the oscillating dependence of the final charge state of the escaping Atomic Particle on its energy.