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

We explore two-particle transfer reactions as a crucial probe of the occurrence 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 98Zr and 100Zr, 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.(c) 2023 The Author(s). Published by Elsevier B.V. This is an open access article under the CC BY license (http://creativecommons .org /licenses /by /4 .0/). Funded by SCOAP3.

Automated summary

We investigate two-particle transfer reactions to study the occurrence of shape coexistence in shape phase transitions. Calculations of (t,p) reactions are performed for even-even Zirconium isotopes, starting from stable nuclei up to beyond current experimental limits. The results reveal a clear signature of a shape phase transition between 98Zr and 100Zr, indicating the coexistence of a deformed ground state with an excited spherical 0+ state. Furthermore, we demonstrate that two-neutron transfer reactions can discriminate between normal shape phase transitions and the one involving shape coexistence.