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arXiv · 1905.12976

Two-particle transfer processes as a signature of shape phase transition in Zirconium isotopes

J. A. Lay·A. Vitturi·L. Fortunato·Y. Tsunoda·T. Togashi·T. Otsuka
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Abstract

We explore two-particle transfer reactions as a unique probe of the occurence of shape coexistence in shape phase transitions. The (t,p) reactions to the ground state and to excited $0^+$ states are calculated for the isotope chain of even-even Zirconium isotopes starting from stable nuclei up to beyond current experimental limits. Two-particle spectroscopic factors derived from Monte Carlo Shell Model calculations are used, together with the sequential description of the two-particle transfer reaction mechanism. The calculation shows a clear signature for a shape phase transition between $^{98}$Zr and $^{100}$Zr, which displays coexistence of a deformed ground state with an excited spherical $0^+$ state. Furthermore, we show that there is a qualitative difference with respect to the case of a normal shape phase transition that can be discriminated with two-neutron transfer reactions.

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J. A. Lay, A. Vitturi, L. Fortunato, Y. Tsunoda, T. Togashi, T. Otsuka. 2019-05-30. Two-particle transfer processes as a signature of shape phase transition in Zirconium isotopes. https://arxiv.org/abs/1905.12976

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