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arXiv · 1807.09294

Symmetry Restoration in Mixed-Spin Paired Heavy Nuclei

Ermal Rrapaj·A. O. Macchiavelli·Alexandros Gezerlis
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Abstract

The nature of the nuclear pairing condensates in heavy nuclei, specifically neutron-proton (spin-triplet), versus identical-particle (spin-singlet) pairing has been an active area of research for quite some time. In this work, we probe three candidates that should display spin-triplet, spin-singlet, and mixed-spin pairing. Using theoretical approaches such as the gradient method and symmetry restoration techniques, we find the ground state of these nuclei in Hartree-Fock-Bogoliubov theory and compute ground-state to ground-state pair-transfer amplitudes to neighbouring isotopes while simultaneously projecting to specific particle number and nuclear spin values. We identify specific reactions for future experimental research that could shed light on spin-triplet and mixed-spin pairing.

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Ermal Rrapaj, A. O. Macchiavelli, Alexandros Gezerlis. 2019-01-29. Symmetry Restoration in Mixed-Spin Paired Heavy Nuclei. https://doi.org/10.1103/physrevc.99.014321

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