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Related papers: Quarteting and spin-aligned proton-neutron pairs i…

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A study is carried out of the role of the aligned neutron-proton pair with angular momentum J=9 and isospin T=0 in the low-energy spectroscopy of the $N=Z$ nuclei $^{96}$Cd, $^{94}$Ag, and $^{92}$Pd. Shell-model wave functions resulting…

Nuclear Experiment · Physics 2011-07-04 S. Zerguine , P. Van Isacker

Shell model calculations using realistic interactions reveal that the ground and low-lying yrast states of the $N=Z$ nucleus $^{92}_{46}$Pd are mainly built upon isoscalar neutron-proton pairs each carrying the maximum angular momentum J=9…

Nuclear Theory · Physics 2011-08-31 Chong Qi , J. Blomqvist , T. Bäck , B. Cederwall , A. Johnson , R. J. Liotta , R. Wyss

The neutron-neutron and proton-proton pairing correlations have long been recognised to be the dominant many-body correlation beyond the nuclear mean field since the introduction of pairing mechanism by Bohr, Mottelson and Pines nearly 60…

Nuclear Theory · Physics 2016-03-28 Chong Qi , R. Wyss

Shell model calculations reveal that the ground and low-lying yrast states of the $N=Z$ nuclei $^{92}_{46}$Pd and $^{96}$Cd are mainly built upon isoscalar spin-aligned neutron-proton pairs each carrying the maximum angular momentum J=9…

Nuclear Theory · Physics 2012-03-09 C. Qi , R. J. Liotta , R. Wyss

Unlike their lighter counterparts, most odd-odd N=Z nuclei with mass A > 40 40 have ground states with isospin T=1, suggesting an increased role for the isovector pairing interaction. A simple SO(5) seniority-like model of this interaction…

Nuclear Theory · Physics 2008-11-26 J. Engel , K. Langanke , P. Vogel

The seniority scheme has been shown to be extremely useful for the classification of nuclear states in semi-magic nuclei. The neutron-proton ($np$) correlation breaks the seniority symmetry in a major way. As a result, the corresponding…

Nuclear Theory · Physics 2012-10-03 C. Qi , J. Blomqvist , T. Bäck , B. Cederwall , A. Johnson , R. J. Liotta , R. Wyss

The isoscalar proton-neutron pairing and isovector pairing, including both isovector proton-neutron pairing and like-particle pairing, are treated in a formalism which conserves exactly the particle number and the isospin. The formalism is…

Nuclear Theory · Physics 2015-07-16 N. Sandulescu , D. Negrea , D. Gambacurta

Rotating $N=Z$ nuclei in the mass $A=58-80$ region have been studied within the framework of isovector mean field theory. Available data is well and systematically described in the calculations. The present study supports the presence of…

Nuclear Theory · Physics 2008-11-26 A. V. Afanasjev

It is argued that $N\sim Z$ nuclei with $90\leq A\leq100$ can be interpreted in terms of aligned neutron--proton pairs with angular momentum $J=2j$ and isospin T=0. Based on this observation, a version of the interacting boson model is…

Nuclear Theory · Physics 2015-06-05 P. Van Isacker

A review is given of attempts to describe nuclear properties in terms of neutron--proton pairs that are subsequently replaced by bosons. Some of the standard approaches with low-spin pairs are recalled but the emphasis is on a recently…

Nuclear Theory · Physics 2015-06-17 P. Van Isacker

Isoscalar (T=0,J=1) and isovector (T=1,J=0) pairing correlations in the ground state of self-conjugate nuclei are treated in terms of alpha-like quartets built by two protons and two neutrons coupled to total isospin T=0 and total angular…

Nuclear Theory · Physics 2015-06-23 M. Sambataro , N. Sandulescu , C. W. Johnson

We show that the correlations generated in the ground state of $N=Z$ nuclei by the isovector and isoscalar pairing forces can be treated with high precision as a condensate of alpha-like quartets. To treat these correlations, the quartet…

Nuclear Theory · Physics 2016-06-22 M. Sambataro , N. Sandulescu

Neutron-proton (np-) pairing is expected to play an important role in the N Z nuclei. In general, it can have isovector and isoscalar character. The existence of isovector np-pairing is well established. On the contrary, it is still debated…

Nuclear Theory · Physics 2017-08-23 A. V. Afanasjev

We propose a particle number conserving formalism for the treatment of isovector-isoscalar pairing in nuclei with $N>Z$. The ground state of the pairing Hamiltonian is described by a quartet condensate to which is appended a pair condensate…

Nuclear Theory · Physics 2018-12-26 D. Negrea , P. Buganu , D. Gambacurta , N. Sandulescu

We provide a description of odd-odd self-conjugate nuclei in the sd shell in a formalism of collective quartets and pairs. Quartets are four-body structures carrying isospin T=0 while pairs can have either T=0 or T=1. Both quartets and…

Nuclear Theory · Physics 2016-11-23 M. Sambataro , N. Sandulescu

We discuss the treatment of isovector pairing by an alpha-like quartet condensate which conserves exactly the particle number, the spin and the isospin. The results show that the quartet condensate describes accurately the isovector pairing…

Nuclear Theory · Physics 2011-09-23 N. Sandulescu , J. Dukelsky , D. Negrea

We show that fully aligned neutron-proton pairs play a crucial role in the low-energy spectroscopy of nuclei. with valence nucleons in a high-j orbital. Their dominance is valid in nuclei with valence neutrons and protons in different…

Nuclear Theory · Physics 2018-04-11 Y. H. Kim , M. Rejmund , P. Van Isacker , A. Lemasson

The $T$=2 excitations in even-even $N$=$Z$ nuclei are calculated within the isospin cranked mean-field approach. The response of pairing correlations to rotation in isospace is investigated. It is shown that whereas the isovector pairing…

Nuclear Theory · Physics 2009-11-06 W. Satuła , R. Wyss

We have performed shell-model calculations for nuclei below 100Sn, focusing attention on the two N=Z nuclei 96Cd and 92Pd, the latter having been recently the subject of great experimental and theoretical interest. We have considered nuclei…

Nuclear Theory · Physics 2012-09-25 L. Coraggio , A. Covello , A. Gargano , N. Itaco
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