Inverted level populations of hydrogen atoms in ionized gas

Thermodynamic properties of the ionized gas 3He

In this article, we have calculated some thermodynamic properties for a system consisting of singy ionized 3He atoms and their corresponding removed electrons by employing the second quantization method at finite temperature. To perform the calculations, we have considered the kinetic term, and Coulomb interaction between the particles in our Hamiltonian. The calculated properties are free ener...

Long-range interactions of copper and silver atoms with hydrogen, helium, and rare-gas atoms

Dispersion interactions of the ground and resonantly excited states of Cu and Ag with a number of buffer gases are determined. The valence excitation spectrum was calculated by diagonalizing a semiempirical Hamiltonian in a large-dimension single-electron basis. The core made a significant contribution to the C6 and C8 dispersion coefficients for both copper and silver. Oscillator strengths and...

The Order of Electron Shells in Ionized Atoms.

Radiative feedback from ionized gas

H2 formation in metal-free gas occurs via the intermediate H − or H+2 ions. Destruction of these ions by photodissociation therefore serves to suppress H2 formation. In this paper, I highlight the fact that several processes that occur in ionized primordial gas produce photons energetic enough to photodissociate H− or H+2 and outline how to compute the photodissociation rates produced by a part...

Pressure of a partially ionized hydrogen gas: numerical results from exact low temperature expansions

We consider a partially ionized hydrogen gas at low densities, where it reduces almost to an ideal mixture made with hydrogen atoms in their ground-state, ionized protons and ionized electrons. By performing systematic low-temperature expansions within the physical picture, in which the system is described as a quantum electron-proton plasma interacting via the Coulomb potential, exact formulae...