Kesteloot, N.García Ramos, José EnriqueZielińska, M.2015-12-152015-12-152015Kesteloot, N., García Ramos, J.E., Zielińska, M... [et. al.]: "Deformation and mixing of coexisting shapes in neutron-deficient polonium isotopes". Physical Review C. Vol. 92, n. 5, 054301, (2015). DOI: 10.1103/PhysRevC.92.0543010556-28131089-490X (electrónico)http://hdl.handle.net/10272/11494Coulomb-excitation experiments are performed with postaccelerated beams of neutron-deficient Po196,198,200,202 isotopes at the REX-ISOLDE facility. A set of matrix elements, coupling the low-lying states in these isotopes, is extracted. In the two heaviest isotopes, Po200,202, the transitional and diagonal matrix elements of the 2+1 state are determined. In Po196,198 multistep Coulomb excitation is observed, populating the 4+1,0+2, and 2+2 states. The experimental results are compared to the results from the measurement of mean-square charge radii in polonium isotopes, confirming the onset of deformation from Po196 onwards. Three model descriptions are used to compare to the data. Calculations with the beyond-mean-field model, the interacting boson model, and the general Bohr Hamiltonian model show partial agreement with the experimental data. Finally, calculations with a phenomenological two-level mixing model hint at the mixing of a spherical structure with a weakly deformed rotational structure.engAtribución-NoComercial-SinDerivadas 3.0 Españahttp://creativecommons.org/licenses/by-nc-nd/3.0/es/journal article10.1103/PhysRevC.92.054301open access