1. Highly ionised heavy ion plasmas.
- Author
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Cavenago, M.
- Subjects
- *
HEAVY ions , *THERMODYNAMIC equilibrium , *ELECTRON distribution , *PLASMA astrophysics , *AUGER effect , *ELECTRON temperature - Abstract
The charge state distribution (CSD) of multiply ionised optically thin plasmas may deviate greatly from thermal equilibrium, so that rate equations and their approximate analytical solutions are necessary to classify different CSDs. Thermal equilibrium is compared with several cases ranging from the case of well confined ions (similar to coronal plasma) to broader CSDs, typical of laboratory plasmas, in particular ion sources, where ion confinement time τ0 and/or electron density ne is poor; electron temperature is limited to a few keV. After discussing updated ionisation rates [Arnaud and Raymond, Astrophys. Jour., 391, 394 (1992)], a new solution for the CSD is worked out in term of the parameter x = τ0ne/nτcr, which reduces to a double exponential distribution named li-de for x → 0 and to a corona equilibrium for x → ∞; for x ≅ 1 a CSD sharper than li-de is found. © 2004 American Institute of Physics [ABSTRACT FROM AUTHOR]
- Published
- 2004
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