Fine-structure energies for the 1[ital s]2[ital s] [sup 3][ital S]--1[ital s]2[ital p] [sup 3][ital P] transition in heliumlike Ar[sup 16+]

Journal Article · Wed Mar 01 04:00:00 EST 1995 · Physical Review A; (United States)

DOI:https://doi.org/10.1103/PhysRevA.51.1905· OSTI ID:6401968

Kukla, K W; Livingston, A E ^[1]; Suleiman, J; Berry, H G; Dunford, R W; Gemmell, D S; Kanter, E P ^[2]; Cheng, S; Curtis, L J ^[3]

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1. Department of Physics, University of Notre Dame, Notre Dame, Indiana 46556 (United States)
2. Physics Division, Argonne National Laboratory, Argonne, Illinois 60439 (United States)
3. Department of Physics, University of Toledo, Toledo, Ohio 43606 (United States)

We have measured the 1[ital s]2[ital s] [sup 3][ital S][sub 1]--1[ital s]2[ital p] [sup 3][ital P][sub 0] and 1[ital s]2[ital s] [sup 3][ital S][sub 1]--1[ital s]2[ital p] [sup 3][ital P][sub 2] fine-structure transition wavelengths in the heliumlike Ar[sup 16+] ion using the beam-foil spectroscopy technique with position-sensitive photon detection. The wavelength results are 559.944(16) A for the [ital J]=1--2 transition and 661.533(18) A for the [ital J]=1--0 transition, which correspond to measurement precisions of about 2[times]10[sup [minus]5] a.u. in the transition energies. These values are sensitive to the relativistic contributions in the transition energies to [lt]500 ppm and to the total QED corrections to [lt]0.5%. The measurements confirm the significance of ([ital Z][alpha])[sup 4]-dependent relativistic corrections to the [ital n]=2 state fine structures suggested by recent calculations. The small remaining discrepancies between these measurements and the accurate theoretical values suggest that the magnitude of uncalculated higher-order QED terms is about 0.15([ital Z][alpha])[sup 4] a.u. Our experimental results disagree with an earlier recoil-ion measurement for the [sup 3][ital S][sub 1]-- [sup 3][ital P][sub 0] transition wavelength.

• DOE Contract Number: FG02-92ER14283; FG05-88ER13958; W-31109-ENG-38
• OSTI ID: 6401968
• Journal Information: Physical Review A; (United States), Journal Name: Physical Review A; (United States) Vol. 51:3; ISSN 1050-2947; ISSN PLRAAN
• Country of Publication: United States
• Language: English

Related Subjects

664300* -- Atomic & Molecular Physics-- Collision Phenomena-- (1992-)
74 ATOMIC AND MOLECULAR PHYSICS
ACCURACY
ARGON IONS
ATOMS
BEAMS
CHARGED PARTICLES
ELECTRODYNAMICS
EMISSION SPECTRA
FIELD THEORIES
FINE STRUCTURE
FOILS
HELIUM IONS
ION BEAMS
IONS
ISOELECTRONIC ATOMS
MULTICHARGED IONS
QUANTUM ELECTRODYNAMICS
QUANTUM FIELD THEORY
SPECTRA
TARGETS