Photoionization of Li and radiative recombination of Li+ in Debye plasmas

Abstract

The photoionization cross sections in the photoelectron energy below 2 Ry are calculated for the ground and n≤4 excited states of Li embedded in plasma environments and the radiative-recombination (RR) rate coefficients for Li+ were presented for temperature T=100–32 000 K in a wide range of plasma parameters. The plasma screening interaction is described by the Debye–Hückel model and the energy levels and wave functions including both the bound and continuum states are calculated by solving the Schrödinger equation numerically in a symplectic integration scheme. The screening of Coulomb interactions remarkably changes the photoionization cross sections near the ionization threshold, and especially for the ns states, the Cooper minimum is uncovered and shifted to the higher energy as the screening interaction increases. The RR rate coefficients at low temperature have a complex variation on the Debye lengths; whereas at higher temperature the RR rate coefficients decrease with the increasing of screening effects. Comparison of present results with those of other authors when available is made.

Influence of Debye plasmas on photoionization of Li-like ions: Emergence of Cooper minima

“…It has been well known that there is no Cooper minimum existing in cross-section curves of ground-state lithium, even though the 2s state wave function of lithium has one node. The existence of Cooper minimum in plasma-embedded lithium also has been demonstrated by the theoretical work of Qi et al [13]. * cylin@pub.iams.sinica.edu.tw The Cooper minima occurring in photoionization cross sections of neutral atoms without screening of plasmas are realized by the departure of discrete and continuum wave functions from hydrogen-like behavior, because the hydrogen atom shows no minima in any state.…”

“…The plasma environments are anticipated to affect the atomic processes significantly due to screening effects. In recent years, there has been considerable effort devoted to investigations of atomic photoionization processes in plasma environments [9][10][11][12][13], because photoionization is extremely sensitive to the details of atomic structure and electronic correlation effects.…”

Non-resonant elastic scattering of low-energy photons by atomic sodium confined in quantum plasmas

“…atoms are injected for diagnostics of fusion edge plasmas 9,10 and extreme ultraviolet radiation from laser-produced alkali plasmas are important for surface morphology applications. 11 Recent years have seen a number of theoretical studies [12][13][14][15][16][17][18] pertaining to the photoionization and the radiative recombination processes, the multipole polarizabilities, and the electronic structures and transition properties of alkali atoms confined in WCPs. It is well-known that the elastic scattering of photons 19,20 by the bound electron(s) of atoms and molecules is one of the fundamental modes of interaction between electromagnetic radiation and matter.…”

Dynamic multipole polarizabilities of Li and Na atoms interacting with Debye potentials

“…For details of the symplectic algorithm for determinations of eigen-energies and wave functions, interested readers are referred to the previously published articles [1,2,[37][38][39][40][41][42][43][44][45].…”

“…It is now well-described that the symplectic integration scheme would be a better technique to obtain solutions of general purpose ordinary differential equations. Successful applications and useful demonstrations of the symplectic integration schemes in different areas of physical sciences would be found from the published articles [37][38][39][40][41][42][43][44][45]. We employ the pseudostate summation method [44][45][46] to obtain the dynamic multipole polarizabilities of Li (2s 2 S) and Na (3s 2 S).…”