A calculation model to half-life estimate of two-proton radioactive decay process

O A P Tavares, Emil Medeiros

Resumo


Partial half-life of the radioactive decay by the two-proton emission mode has been estimated for proton-rich nuclei of mass number 18 < A < 68 by a model based on the quan-tum mechanical tunneling mechanism through a potential barrier. The Coulomb, centrifugal and overlapping contributions to the barrier have been considered within the spherical nucleus ap-proximation. The present calculation method has shown adequate in reproducing the existing experimental half-life data for 19Mg, 45Fe, 48Ni, and 54Zn 2p-emitter nuclides within a factor six. For 67Kr parent nucleus the calculated partial 2p-decay half-life has been found ten times greater than the recent, unique measured value at RIKEN Nishina Center. Prediction for new, yet unmeasured cases of two-proton radioactivity are also reported.

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