electromagnetic interactions. The São Paulo Nuclear Spectroscopy with Light Ions Group has

Angular distributions for the inelastic scattering of 13 MeV deuterons were obtained for states of 99, 101Ru at low excitation energies at the São Paulo Pelletron Accelerator – Enge Magnetic Spectrograph facility. The excellent resolution of ~ 8 keV achieved was important for the good definition of the minimum of the Coulomb-Nuclear Interference (CNI) in the angular distribution. This, in turn, permitted the characterization of the parentage of the states in the odd nuclei with respect to the first quadrupole excitations of the cores through a macroscopic analysis. The analysis employs the Distorted Wave Born Approximation formalism, taking the Deformed Optical Model as transition potential, under well established global optical parameters. Values of the mass deformation length NLδ and the ratio between charge and mass deformation lengths C2 were extracted by fitting the predictions to the experimental angular distributions. The values of C2 are larger than 1.2 in 99Ru and 1.3 in 101Ru, indicating a decrease as a neutron pair is added, of the contribution of the neutrons relative to that of the protons, in the first quadrupole excitation in the odd isotopes, when compared to that previously measured in the even ones