Early onset of deformation in the neutron-deficient polonium isotopes

In-source laser spectroscopy has been performed at CERN-ISOLDE with the RILIS laser ion source on 191–204,206,208–211,216,218Po. New information on the β decay of 199Po were extracted in the process, challenging previous results. Large-scale atomic calculations were performed to extract the changes in the mean-square charge radius δr2 from the isotope shifts. The δr2 for the even-A isotopes reveal a large deviation from the spherical droplet model for N < 116.

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