CORE-SHIELDING EFFECTS ON PHOTOEXCITATION OF THE HG-LIKE IONS

Excitation energies and oscillator strengths from the ground S-1(0) le vel to the first P-3(1)o and P-1(1)o levels of Hg-like ions are calcul ated by using the multiconfiguration relativistic random-phase approxi mation including excitation channels from core electrons. The core-exc itation channels account for the core-shielding effects in an db initi o manner. The discrepancies between the theoretical and experimental r esults are much reduced for the excitation oscillator strengths and 3P (1)(o)-P-1(1)o separations but more enhanced for the excitation energi es when these core-excitation channels are taken into account. Systema tic trends along the sequence are discussed both for the excitation en ergies and oscillator strengths. The effects of core shielding and cor e polarization are discussed.