Resonance and intermediate-coupling effects in electron scattering with highly charged ions. I. Collision strengths for Fe/sup 24 +/, Se/sup 32 +/, and Mo/sup 40 +/

Journal Article · Sat Oct 01 04:00:00 EDT 1983 · Phys. Rev. A; (United States)

DOI:https://doi.org/10.1103/PhysRevA.28.2113· OSTI ID:5457307

Pradhan, A K

A study of electron-impact excitation of highly charged ions in the helium isoelectronic sequence is reported. Nonresonant, intermediate-coupling collision strengths are computed for transitions up to and including the n = 3 states. With the 13 fine-structure levels, i.e., 1s/sup 2/(/sup 1/S/sub 0/), 1s2s(/sup 3/S/sub 1/;/sup 1/S/sub 0/), 1s2p(/sup 3/P/sub 0,1,2/;/sup 1/P/sub 1/ ), 1s3s(/sup 3/S/sub 1/;/sup 1/S/sub 0/), and 1s3p(/sup 3/P/sub 0,1,2/;/sup 1/P/sub 1/ ), there are 78 different inelastic transitions. Main calculations are carried out in the nine-state distorted-wave approximation including partial waves l< or =15. Relativistic effects are taken into account in the Breit-Pauli approximation. Nine-state close-coupling calculations are also carried out for Fe/sup 24 +/ with l< or =4 at a few energies for comparison (and for later work in paper II). Higher partial waves (l>15) are treated by the Coulomb-Bethe method using accurate relativistic eigenenergies and oscillator strengths for the target ions. The Z dependence of the departure from LS coupling is investigated. Present results are in good general agreement with previous calculations where available, but some discrepancies are noted or clarified. Collision strengths are tabulated at energies from near the excitation energy of the n = 3 complex to sufficiently high energies to enable rate coefficients to be computed. For transitions to the n = 3 levels and for transitions where resonances are not important, the present values should yield reasonably accurate excitation rates (resonances are considered in paper II).

• Research Organization: Department of Physics, University of Windsor, Windsor, Ontario 93P4, Canada
• OSTI ID: 5457307
• Journal Information: Phys. Rev. A; (United States), Journal Name: Phys. Rev. A; (United States) Vol. 28:4; ISSN PLRAA
• Country of Publication: United States
• Language: English

Related Subjects

640304* -- Atomic
Molecular &amp; Chemical Physics-- Collision Phenomena
74 ATOMIC AND MOLECULAR PHYSICS
CHARGED PARTICLES
COLLISIONS
COUPLING
CROSS SECTIONS
DISTORTED WAVE THEORY
ELECTRON COLLISIONS
ELECTRON-ION COLLISIONS
ENERGY-LEVEL TRANSITIONS
EXCITATION
FINE STRUCTURE
INTERMEDIATE COUPLING
ION COLLISIONS
IONS
IRON IONS
MOLYBDENUM IONS
MULTICHARGED IONS
PARTIAL WAVES
PLASMA DIAGNOSTICS
RESONANCE
SELENIUM IONS