Fine structure of the 1s2s2p /sup 4/P/sup o/ and 1s2p/sup 2/ /sup 4/P doubly excited states in lithiumlike carbon, nitrogen, and oxygen

Journal Article · Thu Jun 01 04:00:00 EDT 1978 · Phys. Rev., A; (United States)

DOI:https://doi.org/10.1103/PhysRevA.17.1966· OSTI ID:6825935

Livingston, A E; Berry, H G

The fine structure of the 1s2s2p /sup 4/P/sup o/-1s2p/sup 2/ /sup 4/P multiplet in the doubly excited quartet system of three-electron C IV, N V, and O VI has been measured using the method of beam-foil spectroscopy. The fine-structure splittings have been determined to within approx. 5 cm/sup -1/ in both the upper and lower states of each ion, and the absolute transition wavelengths have been measured to within approx. 0.1 A (approx. 10/sup -3/ eV). The wavelength results show that existing relativistic and nonrelativistic energy separations calculated for these /sup 4/P states are inaccurate by approx. 1% for Z = 6--8, and that calculations of the fine-structure splittings are inaccurate by (10--20) % for 1s2s2p /sup 4/P/sup o/ and by > or approx. = 20% for 1s2p/sup 2/ /sup 4/P. Lifetimes have also been measured for the J = 5/2, 3/2, and 1/2 levels of 1s2p/sup 2/ /sup 4/P. Differential metastability is found to be a characteristic feature of these core-excited fine-structure states in all three ions. Comparison with calculated autoionization and K x-ray transition rates for Z = 7 and 8 indicates that the 1s2p/sup 2/ /sup 4/P/sub 5/2/ lifetime is determined essentially by its autoionization rate to the doublet continuum through magnetic interactions, whereas the J = 3/2 and 1/2 states decay at a slower rate that is more characteristic of the /sup 4/P/sup o/-/sup 4/P radiative transition rate.

• Research Organization: Argonne National Laboratory, Argonne, Illinois 60439
• OSTI ID: 6825935
• Journal Information: Phys. Rev., A; (United States), Journal Name: Phys. Rev., A; (United States) Vol. 17:6; ISSN PLRAA
• Country of Publication: United States
• Language: English

Related Subjects

640304* -- Atomic
Molecular & Chemical Physics-- Collision Phenomena
74 ATOMIC AND MOLECULAR PHYSICS
ATOM COLLISIONS
ATOMIC IONS
BEAMS
CARBON IONS
CHARGED PARTICLES
COLLISIONS
ENERGY LEVELS
EXCITED STATES
FINE STRUCTURE
ION BEAMS
ION COLLISIONS
ION SPECTROSCOPY
ION-ATOM COLLISIONS
IONS
NITROGEN IONS
OXYGEN IONS
SPECTROSCOPY