AN EXPANSION METHOD FOR CALCULATING ATOMIC PROPERTIES. X. l/sub s/$sup 2$ $sup 1$S--1snp$sup 1$P TRANSITIONS OF THE HELIUM SEQUENCE.

摘要: The electric dipole matrix elements connecting the 1 s 2 S and snp P states of helium isoelectronic sequence are calculated exactly to first order in inverse powers nuclear charge Z differences from Hartree-Fock approximation shown correspond virtual transitions electrons. Comparison oscillator strengths predicted by a screening with more accurate values reveals regular variation error contained approximation, correction which allows prediction probabilities – for all n within probable 2% (table 5). Values photoionization cross-sections at spectral heads also presented.