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arXiv · 2105.08136

$α$-like quartetting in the excited states of proton-neutron pairing Hamiltonians

M. Sambataro·N. Sandulescu
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Abstract

Previous studies have shown that the ground state of systems of nucleons composed by an equal number of protons and neutrons interacting via proton-neutron pairing forces can be described accurately by a condensate of $α$-like quartets. Here we extend these studies to the low-lowing excited states of these systems and show that these states can be accurately described by breaking a quartet from the ground state condensate and replacing it with an "excited" quartet. This approach, which is analogous to the one-broken-pair approximation employed for like-particle pairing, is analysed for various isovector and isovector-isoscalar pairing

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M. Sambataro, N. Sandulescu. 2021-05-17. $α$-like quartetting in the excited states of proton-neutron pairing Hamiltonians. https://doi.org/10.1016/j.physletb.2021.136476

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