Open M-shell Opacity of Bromine Plasma in Comparison of the Detailed Level Accounting Model with the Average Atom Model

The open M-shell opacity of a hot bromine plasma has been calculated by using a detailed level accounting (DLA) model. One-electron orbitals obtained by solving the fully relativistic Dirac--Fock equations are used to obtain the atomic levels and the radiative transition oscillator strengths. Only the level mixing within the same electron configuration is considered to reduce the complexity of the calculations. Detailed comparisons have been made between the results of the DLA and average atom (AA) models. Good agreements are found for both the M-shell transition arrays and the Planck mean opacity but there are differences for the line positions in the 2p → 3d absorption region due to the statistical treatment for the one-electron orbitals in the AA model.