Radiative rates and electron impact excitation rate coefficients for Ne-like selenium, Se XXV

Journal Article · Fri Jul 15 00:00:00 EDT 2011 · Atomic Data and Nuclear Data Tables

DOI:https://doi.org/10.1016/j.adt.2011.03.004· OSTI ID:21592587

Wang, K; Huang, M; Wang, Y S; Zou, Y M

In this article we report calculations of energy levels, radiative rates, electron impact collision strengths, and effective collision strengths for transitions among the 241 fine-structure levels arising from 2l{sup 8} and 2l{sup 7}n{sup '}l{sup '} (n{sup '{<=}}6 and l{sup '{<=}}n{sup '}-1) configurations of Ne-like Se XXV using the Flexible Atomic Code. Energy levels and radiative rates are calculated within the relativistic configuration-interaction method. Direct excitation collision strengths are calculated using the relativistic distorted-wave approximation and high-energy collision strengths are obtained in the relativistic plane-wave approximation. Resonance contributions through the relevant Na-like doubly-excited configurations 2l{sup 7}n'l'n''l'' (3{<=}n'{<=}7, l'{<=}n'-1, n'{<=}n''{<=}50, and l''{<=}8) are explicitly taken into account via the independent-process and isolated-resonance approximation using distorted waves. Resonant stabilizing transitions and possibly important radiative decays from the resonances toward low-lying autoionizing levels are considered. In addition, the resonance contributions from Na-like 2l{sup 6}3l'3l'''n''' (n'''=3-6) configurations are included and found to be predominant for many transitions among the singly-excited states in Ne-like Se XXV. We present the radiative rates, oscillator strengths, and line strengths for all electric dipole, magnetic dipole, electric quadrupole, magnetic quadrupole, electric octopole, and magnetic octopole transitions among the 241 levels. The effective collision strengths are reported for all 28920 transitions among the 241 levels over a wide temperature range up to 10 keV. To assess the reliability and accuracy of the present collisional data, we have performed a 27-state close-coupling calculation, employing the Dirac R-matrix theory. The results from the close-coupling calculation and the independent-process calculation for the identical target states are found to be in good agreement. - Highlights: {yields} Radiative and collisional atomic data are presented for the lowest 241 fine-structure levels in Ne-like Se. {yields} Calculations are performed using the FAC package. {yields} Resonances enhance significantly a large amount of transitions. {yields} Radiative damping effects are significant for many transitions. {yields} Close-coupling effects are small in Ne-like Se.

• OSTI ID: 21592587
• Journal Information: Atomic Data and Nuclear Data Tables, Journal Name: Atomic Data and Nuclear Data Tables Journal Issue: 4 Vol. 97; ISSN ADNDAT; ISSN 0092-640X
• Country of Publication: United States
• Language: English

Related Subjects

73 NUCLEAR PHYSICS AND RADIATION PHYSICS
74 ATOMIC AND MOLECULAR PHYSICS
APPROXIMATIONS
BEAMS
CALCULATION METHODS
COLLISIONS
CONFIGURATION INTERACTION
DECAY
DIPOLES
DISTORTED WAVE THEORY
ELECTRIC DIPOLES
ELECTRON BEAMS
ELECTRON COLLISIONS
ELEMENTS
ENERGY LEVELS
ENERGY RANGE
ENERGY-LEVEL TRANSITIONS
EXCITATION
EXCITED STATES
FINE STRUCTURE
KEV RANGE
KEV RANGE 01-10
LEPTON BEAMS
MAGNETIC DIPOLES
MATRICES
MULTIPOLES
OSCILLATOR STRENGTHS
PARTICLE BEAMS
PARTICLE DECAY
R MATRIX
RADIATIVE DECAY
RELATIVISTIC RANGE
RESONANCE
SELENIUM
SEMIMETALS
WAVE PROPAGATION