Shape coexistence and isospin symmetry along N=Z

The region of proton-rich nuclei around the N=Z offers a rich testing ground for various nuclear models. Rapid shape changes have been observed between from prolate deformation in 76Kr to an oblate ground state in 72Kr. Based on the comparison with its mirror nucleus 70Se, an oblate shape is expected for 70Kr. Breaking of isospin symmetry as well as the proximity to the proton drip line however, may lead to measurable differences in the excitation energy spectrum as well as the quadrupole collectivity of the A=70 mirror pair 70Kr and 70Se. 70Kr has been studied at the RIBF facility using Coulomb excitation and neutron removal reactions using the BigRIPS fragment separator to select 70-72Kr beams. Reaction products were identified in the ZeroDegree spectrometers, while emitted gamma-rays were detected in the DALI2 array. Detailed spectroscopic information on 70Kr and measurements of the B(E2) value will be presented and discussed in comparison to the mirror nucleus 70Se and theoretical calculations. These results give important insights in the evolution of shape coexistence and isospin symmetry across the N=Z line.