Related papers: Models for Pairing Phenomena
The onset of 1S0 proton spin-singlet pairing in neutron-star matter is studied in the framework of the BCS theory including medium polarization effects. The strong three-body coupling of the diproton pairs with the dense neutron environment…
Asymptotic form of neutron Cooper pair penetrating to the exterior of nuclear surface is investigated with the Bogoliubov theory for the superfluid Fermions. Based on a two-particle Schr\"{o}dinger equation governing the Cooper pair wave…
The dineutron correlations and the crossover from superfluidity of neutron Cooper pairs in the $^1S_0$ pairing channel to Bose-Einstein condensation (BEC) of dineutron pairs in both symmetric and neutron matter are studied within the…
[Background] Nuclear pairing is a well-established many-body correlation, particularly among like particles in a spin-singlet state. However, the strength of spin-triplet proton-neutron (pn) pairing in nuclei has remained a long-standing…
A two-dimensional (2D) assembly of noninteracting, temperature-dependent, composite-boson Cooper pairs (CPs) in chemical and thermal equilibrium with unpaired fermions is examined in a binary boson-fermion statistical model as the…
This thesis explores nuclear systems under extreme conditions of isospin asymmetry and strong magnetic fields. Its first chapter is devoted to the phase diagram of isospin-asymmetrical nuclear matter in the density-temperature plane. Four…
Microscopic theories beyond mean-field are developed to include pairing, in-medium nucleon-nucleon collisions as well as effects of initial fluctuations of one-body observables on nuclear dynamics. These theories are applied to nuclear…
The present contribution reviews recent advances made toward a microscopic understanding of superfluidity in nuclei using many-body methods based on the BCS ansatz and low-momentum inter-nucleon interactions, themselves based on chiral…
A two-dimensional (2D) assembly of noninteracting, temperature-dependent, composite-boson Cooper pairs (CPs) in chemical and thermal equilibrium with unpaired fermions is examined in a binary boson-fermion statistical model as the…
By adopting a $T$-matrix based method within $G_0G$ approximation for the pair susceptibility, we studied the effects of pairing fluctuation on the BCS-BEC crossover in symmetric nuclear matter. The pairing fluctuation induces a pseudogap…
A survey of algebraic approaches to various problems in nuclear physics is given. Examples are chosen from pairing of many-nucleon systems, nuclear structure, fusion reactions below the Coulomb barrier, and supernova neutrino physics to…
On the basis of time-dependent mean-field picture, we discuss the nature of the low-frequency quadrupole vibrations from small-amplitude to large-amplitude regimes as representatives of surface shape vibrations of a superfluid droplet…
Pairing plays a central role in nuclear systems. The simplest model for the pairing is the constant-pairing Hamiltonian. The aim of the present paper is to include the continuum single particle level density in the constant pairing…
Departing from the assumption that pairing is induced by an retarded external 'bosonic glue', we reformulate the Bardeen-Cooper-Schrieffer theory of superconductivity as a scaling theory. Conventional superconductors correspond with the…
We formulate a Bardeen-Cooper-Schriffer (BCS) theory of quasiparticles in a degenerate Fermi gas strongly coupled to photons in a optical cavity. The elementary photonic excitations of the system are cavity polaritons, which consist of a…
Nuclear supersymmetry is reviewed and some of its applications and extensions are discussed, together with a proposal for new, more stringent and precise tests to probe the supersymmetry classification, in particular, correlations between…
We investigate pseudo-gap phenomena realized in the BCS pairing model with a long but finite interaction range. We calculate the single-particle self-energy in all order exactly in the temperature range where the superconducting fluctuation…
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.…
Level density $\rho(E,N,Z)$ is calculated for the two-component close- and open-shell nuclei with a given energy $E$, and neutron $N$ and proton $Z$ numbers, taking into account pairing effects within the microscopic-macroscopic approach…
A functional theory based on single-particle occupation numbers is developed for pairing. This functional, that generalizes the BCS approach, directly incorporates corrections due to particle number conservation. The functional is…