Analysis of doubly excited state resonances below the Li(5p) threshold in Li- photodetachment
Abstract
Larger scale eigenchannel R-matrix calculations than those of Pan et al. [Phys. Rev. A 53, 840 (1996)] confirm the prediction of a 2-meV-wide resonance feature at a photon energy of 5.421 eV in the Li (3s) partial cross section resulting from photodetachment of Li-. This resonance was neither clearly observed nor identified in measurements of Ljungblad et al. [Phys. Rev. Lett. 77, 3751 (1996)]. We identify this resonance as a N\{υ\}An=5\{1\}- 6 state [having angular symmetry (K,T)A=(2,0)- or (nλ,nμ,m)=(1,7,0)]. This state, which is forbidden by propensity rules in H- photodetachment, is predicted to be prominent also in the Li(4l) partial cross sections, for l>=1. Besides the 5\{1\}-6 state, the Li(3s) partial cross section in the energy region 20-60 meV below the Li(5p) threshold is dominated by two other doubly excited states, which have been observed in H- photodetachment. Our calculations are in excellent agreement with the measurements of Ljungblad et al. in the energy region from the Li(5p) threshold to 20 meV below.
- Publication:
-
Physical Review A
- Pub Date:
- December 1998
- DOI:
- 10.1103/PhysRevA.58.4997
- Bibcode:
- 1998PhRvA..58.4997L
- Keywords:
-
- 32.80.Gc;
- 31.25.Jf;
- Photodetachment of atomic negative ions;
- Electron correlation calculations for atoms and ions: excited states