Resonant photoionization of singly charged sulfur

Journal Article · Tue Aug 15 00:00:00 EDT 2006 · Physical Review. A

DOI:https://doi.org/10.1103/PHYSREVA.74.022704· OSTI ID:20853065

Tayal, S S ^[1]

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1. Department of Physics, Clark Atlanta University, Atlanta, Georgia 30314 (United States)

Resonance structures in the photoionization of S{sup +} for the removal of a 3p or 3s electron from the ground 3s{sup 2}3p{sup 3} {sup 4}S{sup o} and excited metastable {sup 2}D{sup o} and {sup 2}P{sup o} states have been studied in the B-spline R-matrix approach. The nonorthogonal orbitals have been used for an accurate representation of the initial S{sup +} bound states, the final S{sup 2+} ion plus photoelectron states and S{sup 2+} thresholds. Calculations have been carried out in 17- and 27-state close-coupling approximations. The relativistic effects have been incorporated in the Breit-Pauli Hamiltonian. Photoionization cross sections are dominated by 3s{sup 2}3p{sup 2}({sup 1}D)ns {sup 2}D, 3s{sup 2}3p{sup 2}({sup 1}D)nd {sup 2}F, {sup 2}D, {sup 2}P, and 3s3p{sup 3}({sup 5}S{sup o}, {sup 3}S{sup o}, {sup 3}D{sup o}, {sup 3}P{sup o})np {sup 4}P Rydberg series of autoionizing resonances. The resonance states are identified and analyzed to obtain resonance positions E{sub r}, effective quantum numbers n{sup *}, and widths {gamma}{sub r} using a procedure of eigenphase gradients. The resonance line shape and correlation parameters have also been determined. Photoionization cross sections have been calculated in both length and velocity formulations that exhibit very good agreement (within 5%) with each other for most photon energies. Our results are compared with a recent merged ion-photon beam experiment. Significant discrepancies between the theoretically predicted and experimentally measured resonance structures and continuum cross sections are noted.

• OSTI ID: 20853065
• Journal Information: Physical Review. A, Journal Name: Physical Review. A Journal Issue: 2 Vol. 74; ISSN 1050-2947; ISSN PLRAAN
• Country of Publication: United States
• Language: English

Related Subjects

74 ATOMIC AND MOLECULAR PHYSICS
APPROXIMATIONS
AUTOIONIZATION
BOUND STATE
CATIONS
CORRECTIONS
CORRELATIONS
COUPLING
CROSS SECTIONS
ELECTRONS
GROUND STATES
HAMILTONIANS
METASTABLE STATES
PHOTOIONIZATION
PHOTON BEAMS
PHOTON-ATOM COLLISIONS
PHOTONS
QUANTUM NUMBERS
R MATRIX
RELATIVISTIC RANGE
RESONANCE
RYDBERG STATES
SULFUR IONS