Radiative rates for E1, E2, M1, and M2 transitions in the Br-like ions Sr IV, Y V, Zr VI, Nb VII, and Mo VIII

Abstract

a b s t r a c tEnergies and lifetimes are reported for the lowest 375 levels of five Br-like ions, namely Sr IV, Y V, Zr VI, Nb VII, and Mo VIII, mostly belonging to the 4s 2 4p 5 , 4s 2 4p 4 4ℓ, 4s4p 6 , 4s 2 4p 4 5ℓ, 4s 2 4p 3 4d 2 , 4s4p 5 4ℓ, and 4s4p 5 5ℓ configurations. Extensive configuration interaction has been included and the general-purpose relativistic atomic structure package (grasp) has been adopted for the calculations. Additionally, radiative rates are listed among these levels for all E1, E2, M1, and M2 transitions. From a comparison with the measurements, the majority of our energy levels are assessed to be accurate to better than 2%, although discrepancies between theory and experiment for a few are up to 6%. An accuracy assessment of the calculated radiative rates (and lifetimes) is more difficult, because no prior results exist for these ions.