Weibel Instability in a Bi-Maxwellian Laser Fusion Plasma

Abstract

In this paper, the Weibel instability, driven by the plasma temperature anisotropy, in the corona of high intense laser fusion plasma is studied. The unperturbed electronic distribution function, f, of the anisotropic corona is supposed to be a bi-Maxwellian. That T_∥ = T_⊥ ± W_O, where W_O = ¼ m_ev_O² is the averaged electron quiver energy in the laser electric field. The first and the second anisotropies of f projected on the Legendre polynomials are calculated as a function of the scaling parameter, W_O / T_⊥. The Weibel instability parameters are explicitly calculated as a function of the scaling parameter. For typical parameters of the laser pulse and the fusion plasma, it has been shown that very unstable Weibel modes, γ ≳ 10¹¹ s⁻¹, can be excited in the corona.