Core polarisation corrections to dipole transitions for one valence electron systems in the quantum-defect approximation

Relativistic oscillator strengths for dipole transitions in one valence electron alkali-like atomic systems are determined with Dirac and quasirelativistic quantum-defect radial wave functions. The calculations carried out account explicitly for core polarisation effects. This leads to a change of the usual dipole operator r to r+dc where dc describes the induced dipole moment of the core by the optical electron. Our derivations retain the simplicity of the previous works, namely, that the radial integrals are obtained analytically in a closed and compact form. The numerical results computed for some members of the copper isoelectronic sequence clearly illustrate the importance of including correlation effects in the derivation of the transition matrix elements. The overall agreement between our f values and the reference data is better than without inclusion of polarisation effects.