Core-polarization effects in CuII

Core-polarization and configuration interaction effects are investigated in singly ionized copper. It is shown that these effects are responsible, to a large extent, for the discrepancies observed between recent relativistic Hartree-Pock (HFR) and configuration-interaction (CIV3) calculations and ac curate beam-laser experimental results. A new set of transition rates is ob tained using the HFR + Core Polarization formalism leading to theoretical l ifetime and transition probability values in fair agreement with the experi ment. An indicative calculation performed with the configuration - interact ion code SUPERSTRUCTURE demonstrates the importance of semi-empirical term energy corrections in producing reliable transition rates in a case like th e present one.