Wannier threshold law for two-electron escape in dense high-temperature plasmas

The quantum-mechanical and plasma screening effects on the Wannier ionization threshold law for the two-electron escape into the continuum is investigated in dense high-temperature plasmas. An effective pseudopotential model is applied to describe particle interactions in dense high-temperature plasmas. The screened renormalized electron charge is obtained as a function of the thermal de Broglie wavelength, Debye length, and charge of the residual ion. The screened threshold exponent of the double ionization cross section is also obtained by using the effective screened charge Z(eff). It is found that the quantum-mechanical effect increases the renormalized electron charge, especially, in the short distance region. It is also found that the screened Wannier exponent increases due to the quantum-mechanical effect, especially, when the de Broglie wavelength is comparable to the Bohr radius. In dense high-temperature plasmas, the quantum-mechanical effect is found to be more significant than the plasma screening effect. (c) 2005 Elsevier B.V. All rights reserved.