Nature of the Excited States of the Even-Even 98-108 Ru Isotopes

The positive and negative parity states of the even-even 98 - 108 Ru isotopes are studied within the frame work of the interacting boson approximation model ( IBA-1) . The calculated levels energy, potential energy surfaces, V ( ; ) , and the electromagnetic transition probabilities, B ( E 1) and B ( E 2) , show that ruthenium isotopes are transi- tional nuclei. Staggering effectle, I = 1 , has been observed between the positive and negative parity states in some of ruthenium isotopes. The electric monopole strength, X ( E 0 =E 2) , has been calculated. All calculated values are compared with the available experimental and theoretical data wher reasonable agreement has obtained