Evolution of nuclear ground-state properties of neutron-deficient isotopes around Z=82 from precision mass measurements

High-precision mass measurements of neutron-deficient Tl (A = 184, 186, 190, 193-195, 198) isotopes as well as Pb (A = 202, 208), Fr (A = 207, 208), and Ra (A = 224) are performed with the Penning-trap mass spectrometer ISOLTRAP at ISOLDE/CERN. The improved precision of the mass data now allows the study of subtle odd-even effects. The gradual development of collectivity with the removal of protons from the magic Z = 82 core is analyzed by combining the new mass results with nuclear charge-radii data and mean-field model predictions.