Structure of krypton nuclei and the low-lying positive parity bands in 82Kr

The shapes of even-mass krypton nuclei are studied using a deformed Hartree-Fock calculation with the 56Ni core. It is found that nuclei with A=72-80 are oblate in shape and 82Kr is a transitional nucleus with near prolate oblate degeneracy. The low-lying states and the band crossing in 82Kr are studied by angular momentum projection from the deformed configurations. The compression of energy levels near 6h is seen to be due to the rotation alignment of neutrons in g9/2 orbits of oblate shape.