Damping of plasma-electron oscillations and waves in low-collision electron-ion plasmas

TL;DR

This paper applies a novel asymptotic solution method to analyze damping of high-frequency plasma-electron oscillations in low-collision electron-ion plasmas, revealing a frequency-dependent decrement distinct from low-frequency sound waves.

Contribution

It introduces a new application of the Laplace transform method to derive frequency-dependent damping expressions for plasma-electron oscillations considering Coulomb collisions.

Findings

Damping decrement depends significantly on oscillation frequency .

Derived expressions differ from those used for low-frequency plasma sound.

Results highlight the distinct nature of high-frequency plasma oscillation damping.

Abstract

Previously developed method for finding asymptotic solutions of Vlasov equations using two-dimensional (in coordinate x and time t) Laplace transform is applied to low-collision electron-ion plasmas. Taking into account Coulomb collisions in the limit m_e << m_i, \bar{v_i} << \bar{v_e}, and T_e m_e << T_i m_i, results in the expression for longitudinal high-frequency plasma-electron oscillation/wave decrement essentially depending on oscillation frequency \omega. This expression is quite different from the used one for low-frequency plasma sound, which can be derived using expansion in asymptotically divergent series in \delta/\omega_0, k v_i/\omega_0, where \delta is imaginary part of the frequency \omega=\omega_0+i\delta, and does not reduce to simple expression with some collision frequency \delta\sim\nu^{eff}_{e_i}.