  We study the oblate-prolate shape mixing in the low-lying states of
proton-rich Kr isotopes using the five-dimensional quadrupole collective
Hamiltonian. The collective Hamiltonian is derived microscopically by means of
the CHFB (constrained Hartree-Fock-Bogoliubov) + Local QRPA (quasiparticle
random phase approximation) method, which we have developed recently on the
basis of the adiabatic self-consistent collective coordinate method. The
results of the numerical calculation show the importance of large-amplitude
collective vibrations in the triaxial shape degree of freedom and rotational
effects on the oblate-prolate shape mixing dynamics in the low-lying states of
these isotopes.
