Sotty, C.Zielinska, M.Georgiev, G.Balabanski, D.L.Stuchbery, AndrewBlazhev, A.Bree, N.Chevrier, R.Das Gupta, S.Daugas, J.M.Wenander, F2016-06-140031-9007http://hdl.handle.net/1885/103360Excited states of the neutron-rich nuclei Rb97,99 were populated for the first time using the multistep Coulomb excitation of radioactive beams. Comparisons of the results with particle-rotor model calculations provide clear identification for the ground-state rotational band of Rb97 as being built on the πg9/2 [431]3/2+ Nilsson-model configuration. The ground-state excitation spectra of the Rb isotopes show a marked distinction between single-particle-like structures below N=60 and rotational bands above. The present study defines the limits of the deformed region around A∼100 and indicates that the deformation of Rb97 is essentially the same as that observed well inside the deformed region. It further highlights the power of the Coulomb-excitation technique for obtaining spectroscopic information far from stability. The Rb99 case demonstrates the challenges of studies with very short-lived postaccelerated radioactive beams.ANUP/4011Author/s retain copyright201510.1103/PhysRevLett.115.1725012016-06-14