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Related papers: Exactly Solvable Pairing Models

200 papers

The interplay of pairing is explored for the spectral statistics of nuclear systems with emphasis on the nearest neighbor spacing distributions by employing the kernel density and maximum likelihood estimation techniques. Different…

Nuclear Theory · Physics 2013-06-25 H. Sabri , B. Rashidian Maleki , J. Fouladi , N. Fouladi , M. A. Jafarizadeh

Relative binding energies (RBEs) within three isotopic chains ($^{100-130}$Sn, $^{152-181}$Yb, and $^{181-202 }$Pb) have been studied using the exactly solvable extended pairing model (EPM) \cite{FPan04}. The unique pairing strength $G$,…

Nuclear Theory · Physics 2011-08-19 V. G. Gueorguiev , Feng Pan , J. P. Draayer

Simple methods in the frame work of the broken pair model have been worked out for odd-odd nuclei. The reliability of the model has been tested by reproducing the shell model results of limiting cases in which the broken pair model exactly…

Nuclear Theory · Physics 2007-07-01 I. M. Hamammu , S. Haq , J. M. Eldahomi

A simple approximation to shell model is proposed in which the low energy excitation spectra corresponds to the identical nucleons occupying the same single particle states where they preferred to form pairs for the ground states. We call…

Nuclear Theory · Physics 2008-10-08 S. Haq , Y. Sadeq , I. M. Hamammu

Many exactly solvable models are based on Lie algebras. The pairing interaction is important in nuclear physics and its exact solution for identical particles in non-degenerate single-particle levels was first given by Richardson in 1963.…

Nuclear Theory · Physics 2010-11-30 V. G. Gueorguiev , J. Dukelsky

Thermal behavior of isoscalar and isovector proton-neutron (pn) pairing energies at finite temperature are investigated by the shell model calculations. These pn pairing energies can be estimated by double differences of "thermal" energies…

Nuclear Theory · Physics 2009-11-11 K. Kaneko , M. Hasegawa

Using detailed exact results on pair-correlation functions of Z-invariant Ising models, we can write and run algorithms of polynomial complexity to obtain wavevector-dependent susceptibilities for a variety of Ising systems. Reviewing…

Mathematical Physics · Physics 2011-09-14 Jacques H. H. Perk , Helen Au-Yang

We describe the ground state of the isovector pairing Hamiltonian in self-conjugate nuclei by a product of collective quartets of different structure built from two neutrons and two protons coupled to total isospin T=0. The structure of the…

Nuclear Theory · Physics 2015-06-18 M. Sambataro , N. Sandulescu

A shell-model study of proton-neutron pairing in f - p shell nuclei using a parametrized hamiltonian that includes deformation and spin-orbit effects as well as isoscalar and isovector pairing is reported. By working in a shell-model…

Nuclear Theory · Physics 2015-05-18 Lei Yang , S. Pittel , B. Thakur , N. Sandulescu , A. Poves , Yu-Min Zhao

A shell-model study of proton-neutron pairing in $2p1f$ shell nuclei using a parametrized hamiltonian that includes deformation and spin-orbit effects as well as isoscalar and isovector pairing is reported. By working in a shell-model…

Nuclear Theory · Physics 2015-05-28 Y. Lei , S. Pittel , N. Sandulescu , A. Poves , B. Thakur , Y. M. Zhao

Proton-neutron (p-n) interactions and its various aspects in $N\approx Z$ nuclei of $g_{9/2}$- and $f_{7/2}$ subshell are studied using a schematic model interaction with four force parameters proposed recently. It is shown that the model…

Nuclear Theory · Physics 2009-10-31 K. Kaneko , M. Hasegawa

This manuscript reviews recent results of large scale shell model calculations on N=Z nuclei. The topics discussed include the role proton-neutron pairing on the binding energies of pf-shell nuclei and his influence on backbending rotors;…

Nuclear Theory · Physics 2007-05-23 Gabriel Martinez-Pinedo

We present three classes of exactly solvable models for fermion and boson systems, based on the pairing interaction. These models are solvable in any dimension. As an example we show the first results for fermion interacting with repulsive…

Superconductivity · Physics 2009-11-07 J. Dukelsky , C. Esebbag , P. Schuck

We discuss modeling of nuclear structure beyond the 2-body interaction paradigm. Our first example is related to the need of three nucleon contact interaction terms suggested by chiral perturbation theory. The relationship of the two…

Nuclear Theory · Physics 2019-08-27 V. G. Gueorguiev

We introduce a new class of exactly solvable boson pairing models using the technique of Richardson and Gaudin. Analytical expressions for all energy eigenvalues and first few energy eigenstates are given. In addition, another solution to…

Nuclear Theory · Physics 2009-11-11 A. B. Balantekin , T. Dereli , Y. Pehlivan

A Nilsson mean-field plus extended pairing interaction Hamiltonian with many-pair interaction terms is proposed. Eigenvalues of the extended pairing model are easy to obtain. Our investigation shows that one- and two-body interactions…

Nuclear Theory · Physics 2009-11-10 Feng Pan , V. G. Gueorguiev , J. P. Draayer

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

Pairing effects manifests themselves in many aspects in nuclear systems ranging from finite nuclei to nuclear matter and compact stars. Although with some specific features for nuclear systems, the mechanism of pairing between nucleons in…

Nuclear Theory · Physics 2024-02-07 Xiang-Xiang Sun , Shan-Gui Zhou

The overview of the Exact Pairing technique based on the quasispin symmetry is presented. Extensions of this method are discussed in relation to mean field, quadrupole collectivity, electromagnetic transitions, and many-body level density.…

Nuclear Theory · Physics 2011-04-11 Vladimir Zelevinsky , Alexander Volya