Atomic data and spectral line intensities for Ar XII

Journal Article · Tue Mar 01 04:00:00 EST 2005 · Atomic Data and Nuclear Data Tables

DOI:https://doi.org/10.1016/j.adt.2005.02.001· OSTI ID:20687206

Eissner, W ^[1]; Landi, E ^[2]; Bhatia, A K ^[3]

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1. Institut fuer Theoretische Physik, Teilinstitut 1, Pfaffenwaldring 57/4, D-70550 Stuttgart (Germany)
2. ARTEP Inc., Columbia, MD 21044 (United States)
3. NASA/Goddard Space Flight Center, Greenbelt, MD 20771 (United States)

Electron impact collision strengths are computed for Ar XII in a distorted wave approach and energy levels, oscillator strengths, spontaneous radiative decay rates for the collision target, as well as collisional high energy limits are obtained from an atomic structure calculation. The target expansion comprises the six spectroscopic configurations 2s{sup 2}2p{sup 3}, 2s2p{sup 4}, 2p{sup 5}, 2s{sup 2}2p{sup 2}3s, 2s{sup 2}2p{sup 2}3p, and 2s{sup 2}2p{sup 2}3d, giving rise to 72 fine-structure levels in intermediate coupling. Collision strengths are calculated at five incident energies: 35, 70, 105, 140, and 175 Ry. They are complemented by Coulomb-Born limits towards infinite collision energy for forbidden transitions and line strengths for optically allowed transitions. Excitation rate coefficients are obtained as a function of electron temperature by assuming a Maxwellian electron velocity distribution. Using the excitation rate coefficients and the radiative transition rates, statistical equilibrium equations for level populations are solved at electron densities covering the range of 10{sup 8}-10{sup 14} cm{sup -3} at an electron temperature of log T {sub e}/K = 6.4, corresponding to maximum abundance of Ar XII. Relative spectral line intensities are also calculated.

• OSTI ID: 20687206
• Journal Information: Atomic Data and Nuclear Data Tables, Journal Name: Atomic Data and Nuclear Data Tables Journal Issue: 2 Vol. 89; ISSN ADNDAT; ISSN 0092-640X
• Country of Publication: United States
• Language: English

Related Subjects

73 NUCLEAR PHYSICS AND RADIATION PHYSICS
ABUNDANCE
ARGON
DISTORTED WAVE THEORY
ELECTRON COLLISIONS
ELECTRON DENSITY
ELECTRON TEMPERATURE
ENERGY LEVELS
EQUATIONS
EQUILIBRIUM
EXCITATION
FINE STRUCTURE
FORBIDDEN TRANSITIONS
INTERMEDIATE COUPLING
OSCILLATOR STRENGTHS
RADIATIVE DECAY