Experimental and theoretical studies of lifetimes and transition probabilities for doubly ionized mercury, Hg iii, are reported. Such data are currently of great astrophysical interest because observations with the Goddard high resolution spectrograph on board the Hubble space telescope have shown some 5${\mathit{d}}^9$6s-5${\mathit{d}}^9$6p transitions of Hg iii in the spectrum of the chemically peculiar star χ Lupi. We now report experimental lifetimes for some selected 5${\mathit{d}}^9$6p and 5${\mathit{d}}^8$6s6p levels, determined by beam-foil spectroscopy, and compare the results with theoretical transition probabilities based on relativistic multiconfiguration Dirac-Fock calculations.

• Received 29 July 1992

DOI:https://doi.org/10.1103/PhysRevA.47.884