Semiclassical inelastic electron-ion collisional excitations in nonideal plasmas

Abstract

Semiclassical electron-hydrogenic ion collisional excitation cross sections for 1s→2s and 1s →2p 0 in nonideal plasmas are obtained. An effective pseudopotential model taking into account the plasma screening and collective effects is applied to describe the electron-ion interaction potential in a classical nonideal plasma. The semiclassical straight-line trajectory approximation is applied to the motion of the projectile electron in order to investigate the variation of the total inelastic scattering cross section as a function of the projectile energy, nonideal plasma parameter, and Debye length. It is found that the transition probabilities in ideal plasmas described by the Debye-Hückel potential model are greater than those in nonideal plasmas described by the pseudopotential model. The maximum position of the transition probability gets closer to the target core as the projectile energy increases. It is also found that the scaled cross section decreases when the nonideal plasma parameter (␥) is increased, i.e., the nonideality of plasmas reduces the electron-ion collision cross section.

Two-fluid approach to weak plasma turbulence

“…It is interesting to compare the fluid versions of plasma susceptibilities against the kinetic versions [10,[12][13][14]20]:…”

“…In kinetic theory, thermal speed is defined with a factor 2 higher than that of the fluid theory, v 2 a = 2T a /m a . As discussed in [10,[12][13][14]20], linear and nonlinear susceptibilities in kinetic theory enjoy the following approximate properties:…”

“…The subsequent formulation involves the computation of thirdbody cumulant, ⟨δϕ k ′ ,ω ′ δϕ k−k ′ ,ω−ω ′ δϕ −k,−ω ⟩, which can be done following the customary closure scheme, as explained fully in the author's monograph [20] as well as in other literature [10,[12][13][14]. In this scheme we take each of δϕ k ′ ,ω ′ , δϕ k−k ′ ,ω−ω ′ , and δϕ −k,−ω and write as sums of leading solution that satisfies the linear dispersion relation plus nonlinear correction.…”

“…The weak turbulence theory in plasma physics is a well established research tool that may be employed in numerous studies of nonlinear plasma processes. It was developed by early pioneers of modern plasma physics [1][2][3][4][5][6][7][8][9][10][11], and its further development continues to this day [12][13][14][15][16][17][18][19]. Recently, the present author published a monograph in which a systematic exposition of the subject is presented in a pedagogic manner [20].…”

Linear and nonlinear fluctuations of electron‐temperature‐gradient driven mode and electron acoustic mode in a two‐electron temperature nonthermal magnetized plasma

“…The non‐Maxwellian distributions like kappa, Cairns distribution, are proposed by different researchers on the basis of space data and theoretical work. Everywhere such plasmas have been noticed in the solar wind and planetary magnetospheres [ 20,24 ] ; Yet, their physical origin is still being ascertained.. [ 25–27 ]…”