Dynamic screening effects on electron-ion Coulomb bremsstrahlung in dense plasmas

Abstract

Dynamic plasma screening effects are investigated on classical bremsstrahlung in electron-ion Coulomb scattering in dense plasmas. The electron-ion interaction potential is considered by the introduction of the longitudinal plasma dielectric function. The classical straight-line trajectory method is applied to the path of the projectile electron. The differential bremsstrahlung radiation cross section including the dynamic plasma screening effect is always greater than that including the static plasma screening effect. When the projectile velocity is smaller than the electron thermal velocity the dynamic polarization screening effect becomes the static plasma screening effect. When the projectile velocity is greater than the electron thermal velocity the interaction potential is almost unshielded. It is also found that the static plasma screening formula obtained by the Debye-H\uckel model overestimates the plasma screening effects on the electron-ion Coulomb bremsstrahlung processes in dense plasmas.