The influence of -mixing processes in collisions on atoms’ populations in weakly ionized helium plasmas

The Collisional Atomic Processes of Rydberg Hydrogen and Helium Atoms: Astrophysical Relevance

“…The figure shows a monotonous decrease of rate coefficients with the increases of n and p, and a very slow increase as temperature increases, as concluded in [19,20]. Figure 8.…”

“…The values of excitation rate coefficients for 3000 K ≤ T ≤ 7000 K are from [18]. In the extended region of temperature coefficients are determined here using the semi-classical approach similar to that described in [19] or [20]. The de-excitation rate coefficients K n;n−p (T) are determined according to the principle of thermodynamical balance.…”

“…The de-excitation rate coefficients K n;n−p (T) are determined according to the principle of thermodynamical balance. All necessary expressions are given and explained in Mihajlov et al [20].…”

Excitation and deexcitation processes in atom-Rydberg atom collisions in helium-rich white dwarf atmospheres

“…In accordance with the aim of this work, these rate coefficients are defined as the quantities that determine the mean rates of transition (per single excited atom) caused by the processes (1) and (2) between whole shells with a given n and n ± p. They are determined here using a method similar to that described in Mihajlov et al (2008): the excitation rate coefficients K n;n+p (T ) are calculated directly and numerically in the semi-classical way, while the deexcitation rate coefficients K n;n−p (T ) are determined later according to the principle of thermodynamical balance. All necessary expressions are given in Mihajlov et al (2008). For the DB white dwarf atmospheres considered here, the values of K n;n+p (T ) and K n;n−p (T ), which are used in Eqs.…”

Influence of the (n-n')-mixing processes on the optical properties of the hydrogen clouds in the broad-line region of AGNs

“…where T e = T a = T , T e and T a are the electron and atom temperatures and T is their common value, g n;n+p is the Gaunt factor, R min (n, n + p) and R max (n, n + p) are quantities defined in Mihajlov et al (2008), a 0 is the atomic unit of length, e is the value of electron charge, R is the internuclear distance, and k are the Planck and Boltzmann constants and U 2 (R) is the potential curve of the first excited electronic states of the considered system. X(R) is defined as the function X(R) = Γ(3/2;…”