Transition strengths and multiple band structure inSr82

Abstract
High-spin states in Sr82 were studied using the Fe56 (29Si,2pn) reaction at 95 MeV with a thick 78 mg/cm2 natural Fe (92% Fe56) target. Prompt γ-γ coincidences were measured using three Compton-suppressed Ge detectors at 90° relative to the beam and two at 30°. Directional correlation of oriented nuclei ratios were determined from the 30°– 90° coincidences to assist in assigning spin changes. Nine new states were found, along with 38 new transitions. The Doppler-shift attenuation method was used to determine the mean lifetimes of 22 states in Sr82. The continuum side feeding times into 10 states were determined by comparing the decay line shapes in coincidence with transitions above and below the state under study. The average transition quadrupole moment of 2.8(2) e b in the ground state band of Sr82 would correspond to a relatively large axial quadrupole deformation of β2=0.33, in agreement with theoretical predictions. The excited 2+ band has a higher moment of inertia but a lower transition quadrupole moment of 2.4(2) e b. In the negative-parity bands the quadrupole moment falls from about 3 to 2 e b with increasing spin.

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