Transition probabilities and radiative lifetimes of Mg III

Abstract

There have been calculated transition probabilities for 365 lines arising from 2p⁵ns (n=3,4,5), 2p⁵np (n=3,4), 2p⁵nd (n=3,4), 2p⁵nf (n=4,5) and 2p⁵ 5g configurations of Mg III and radiative lifetimes corresponding to 89 levels. These values were obtained in intermediate coupling (IC) by using ab initio relativistic Hartree–Fock (HFR) calculations. Later, we use the standard method of least square fitting of experimental energy levels for the IC calculations by means of Cowan’s computer codes. The vast majority of the calculated transition probabilities correspond to lines lying in the ultraviolet range (UV) which are of high interest in astrophysics. Our results are compared to those previously reported in the literature. Furthermore, the values of transition probabilities of configuration levels 2p⁵ 4d, 2p⁵nf (n=4,5) and 2p⁵ 5g are presented for the first time. In light of these findings, it is possible to extend the range of wavelengths which allows us to estimate the temperature in plasma diagnostic. In addition, our results for radiative lifetimes have been compared to the available experimental values.