Showing papers by "H. G. Berry published in 2003"

1s2s2p 2 3s 6 P-1s2p 3 3s 6 S o Transitions in O IV

Abstract: The energies and lifetimes of doubly excited sextet states of boron-like O iv, F v, and Ne VI are calculated with the multiconfiguration Hartree-Fock approach, including QED and higher-order corrections, and also with themulticonfiguration Dirac-Fock GRASP code. The wavelengths and transition rates of electric-dipole transitions from the inner-shell excited terms 1s2s2p 2 3s 6 P-1s2p 3 3s 6 S 0 are investigated by beam-foil spectroscopy in the XUV spectral region. The predicted transition wavelengths agree with the experiment. The higher-order corrections, fine structures, and spectrum with high wavelength resolution are found to be critically important in these comparisons. Nine new lines have been identified. The ground sextet states of boronlike atoms are metastable and well above several ionization levels. These are possible candidates for XUV and soft x-ray lasers.

Laser gas-discharge absorption measurements of the ratio of two transition rates in neutral argon

Abstract: The ratio of line strengths for the two argon transitions, 3p{sup 5}({sup 2}P{sub 1/2}{sup o})4s[1/2]{sub 1}{sup o}{yields}3p{sup 5}({sup 2}P{sub 3/2}{sup o})4p[3/2]{sub 2} at wavelength 922.7 nm and 3p{sup 5}({sup 2}P{sub 1/2}{sup o})4s[1/2]{sub 1}{sup o}{yields}3p{sup 5}({sup 2}P{sub 3/2}{sup o})4p[5/2]{sub 2} at wavelength 978.7 nm, is measured in an argon pulsed discharge with the use of a single-mode Ti:sapphire laser. The result 3.29(0.13) is in agreement with our theoretical prediction 3.23 and with a less accurate ratio 2.89(0.43) from the NIST database.