The isotopic evolution of the ground-state nuclear shapes and the systematics
of one-quasiproton configurations are studied in neutron-rich odd-A Yttrium and
Niobium isotopes. We use a selfconsistent Hartree-Fock-Bogoliubov formalism
based on the Gogny energy density functional with two parametrizations, D1S and
D1M. The equal filling approximation is used to describe odd-A nuclei
preserving both axial and time reversal symmetries. Shape-transition signatures
are identified in the N=60 isotopes in both charge radii and spin-parities of
the ground states. These signatures are a common characteristic for nuclei in
the whole mass region. The nuclear deformation and shape coexistence inherent
to this mass region are shown to play a relevant role in the understanding of
the spectroscopic features of the ground and low-lying one-quasiproton states.
Finally, a global picture of the neutron-rich A=100 mass region from Krypton up
to Molybdenum isotopes is illustrated with the systematics of the nuclear
charge radii isotopic shifts.Comment: 21 pages, 14 figures. To be published in Phys. Rev.
