Stopping power in dense, high-temperature plasmas

2003

Physics of Plasmas

The electron-ion bremsstrahlung process in a kappa-Maxwellian distribution plasma is investigated. The Coulomb correction effect on the bremsstrahlung emission rate from the kappa-Maxwellian distribution plasma is investigated as a function of the radiation photon energy for T ʈ ϾT Ќ , T ʈ ϭT Ќ , and T ʈ ϽT Ќ , where T ʈ and T Ќ are the parallel and perpendicular temperatures, respectively. The results show that for low photon energies the Coulomb focusing effects are found to be less significant for low spectral indices when T ʈ ϽT Ќ . However, for high photon energies, the Coulomb correction effects are found to be almost identical for all spectral indices. It is also found that the Coulomb focusing effects for T ʈ ϾT Ќ are more significant than those for T ʈ ϽT Ќ . In addition, the plasma screening and quantum effects on the nonrelativistic electron-ion bremsstrahlung process in strongly coupled semiclassical plasmas are also investigated using the effective screened potential model taking into account the plasma screening effect, as well as the quantum-mechanical effect. The analytic form of the bremsstrahlung radiation cross section in strongly coupled semiclassical plasmas is obtained as a function of the radiation photon energy, electron kinetic energy, thermal de Broglie wavelength, and Debye length. It is found that the quantum effect on the bremsstrahlung radiation cross section is slightly increased with increasing radiation photon energy. The quantum effect on the bremsstrahlung cross section is also found to be more important than the plasma screening effect on the bremsstrahlung process in strongly coupled semiclassical plasmas.

Section: Differential Bremsstrahlung Radiation Cross Section In Smentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

Coulomb focusing and quantum effects on the electron-ion bremsstrahlung processes in plasmas

2003

Physics of Plasmas

“…An integro-differential equation for the effective potential of the particle interaction, taking into account the simultaneous correlations of N particles, has been obtained on the basis of a sequential solution of the chain of Bogolyubov equations for the equilibrium distribution function of particles of a classical nonideal plasma, and an analytical expression for the pseudopotential (Baimbetov et al 1995) of the particle interaction in a nonideal plasma has been obtained by application of the spline approximation. Using the pseudopotential model, taking into account plasma-screening and collective effects (Arkhipov et al 2000a(Arkhipov et al ,b, 2001, the interaction potential V NI (r) between the projectile electron and the target ion with charge Z in a classical nonideal plasma can be written as…”

Section: Classical Bremsstrahlung Cross-sectionmentioning

confidence: 99%

Classical bremsstrahlung radiation from electron–ion encounters in a nonideal plasma

Kim

2002

J. Plasma Phys.

The classical electron–ion Coulomb bremsstrahlung process is investigated in a nonideal plasma. An effective pseudopotential model taking into account plasma-screening and collective effects is applied to describe the electron-ion interaction potential in a nonideal plasma. The screened hyperbolic-orbit trajectory method is applied to the motion of the projectile electron in order to investigate the bremsstrahlung radiation cross-section as a function of the scaled impact parameter, eccentricity, nonideal-plasma parameter, Debye length, projectile energy, and photon energy. It is found that the collective effect reduces the bremsstrahlung radiation cross-section on both the soft- and hard-photon cases. For small impact parameters, the nonideal-plasma effect on the bremsstrahlung radiation cross-section is found to be quite small. It is also found that the maximum position of the bremsstrahlung radiation cross-section gets closer to the target ion with increasing nonideal-plasma effect.

“…In strongly coupled semiclassical plasmas, the interaction potential is cannot be described by the Debye-Hückel-type because of nonideal particle interactions due to collective plasma screening and quantummechanical effects. [11][12][13] Then, the elastic electron-ion collisions in strongly coupled plasmas must be different from those in weakly coupled ideal plasmas. It has been known that the eikonal method 14 -16 has a great advantage since we can obtain the generalized electron wave function in terms of the eikonal phase including various physical properties of the surrounding plasma.…”

Section: Introductionmentioning

confidence: 99%

Collective and quantum effects on elastic electron–ion collisions in strongly coupled semiclassical plasmas

2003

Physics of Plasmas

Collective plasma screening and quantum-mechanical effects on elastic electron–ion collisions in strongly coupled semiclassical plasmas are investigated using the second-order eikonal method. The effective screened potential model taking into account both the plasma screening and quantum effects is applied to describe the elastic electron–ion interactions in strongly coupled semiclassical plasmas. The impact-parameter trajectory method is applied to the path of the projectile electron in order to investigate the variation of the eikonal cross section as a function of the impact parameter, thermal de Broglie wavelength, Debye length, and collision energy. It is found that the collective plasma screening and quantum effects reduce the elastic electron–ion scattering cross section for small impact parameters. However, the quantum effects are found to be less important than the plasma screening effects for large impact parameters.