English
Related papers

Related papers: Using Continuum Level Density in the Pairing Hamil…

200 papers

Pairing correlations and their influence on nuclear properties has been studied within BCS model. Using this theoretical model with inclusion of pairing interaction between nucleons, nuclear level density and entropy of Pd(105,106,107) have…

Nuclear Theory · Physics 2015-05-11 Azam Rahmatinejad , Tayeb Kakavand , Rohallah Razavi

The eastern region of the calcium isotope chain of the nuclei chart is, nowadays, of great activity. The experimental assessment of the limit of stability is of interest to confirm or improve microscopic theoretical models. The goal of this…

Nuclear Theory · Physics 2020-12-02 A. C. Dassie , R. M. Id Betan

We study the correlation energy associated with the pair fluctuations in BCS theory. We use a schematic two-level pairing model and discuss the behavior of the correlation energy across shell closures, including the even-odd differences. It…

Nuclear Theory · Physics 2009-11-06 K. Hagino , G. F. Bertsch

Studies of pairing correlations in ultrasmall metallic grains have commonly been based on a simple reduced BCS-model describing the scattering of pairs of electrons between discrete energy levels that come in time-reversed pairs. This model…

Strongly Correlated Electrons · Physics 2007-05-23 Jan von Delft , Fabian Braun

A semi-microscopic model for nucleon pairing in nuclei is presented starting from the ab intio BCS gap equation with Argonne v18 force and the self-consistent Energy Density Functional Method basis characterized with the bare nucleon mass.…

Nuclear Theory · Physics 2011-08-11 S. S. Pankratov , M. V. Zverev , M. Baldo , U. Lombardo , E. E. Saperstein

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…

Nuclear Theory · Physics 2023-08-16 A. G. Magner , A. I. Sanzhur , S. N. Fedotkin , A. I. Levon , U. V. Grygoriev , S. Shlomo

Recently we proposed a particle-number-conserving theory for nuclear pairing [Jia, Phys. Rev. C 88, 044303 (2013)] through the generalized density matrix formalism. The relevant equations were solved for the case when each single-particle…

Nuclear Theory · Physics 2015-12-09 L. Y. Jia

In this work, a new functional is introduced to treat pairing correlations in finite many-body systems. Guided by the projected BCS framework, the energy is written as a functional of occupation numbers. It is shown to generalize the BCS…

Nuclear Theory · Physics 2015-05-18 Denis Lacroix , Guillaume Hupin

The most essential concept in concurrent multiscale methods involving atomistic-continuum coupling is how to define the relation between atomistic and continuum regions. A well-known coupling method that has been frequently employed in…

Mesoscale and Nanoscale Physics · Physics 2022-07-27 Pouya Towhidi , Manouchehr Salehi

We propose a scheme to perform the variational principle directly on the coherent pair condensate (VDPC). The result is equivalent to that of the so-called variation after particle-number projection, but now the particle number is always…

Nuclear Theory · Physics 2019-01-09 L. Y. Jia

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

We introduce a conditional pair distribution function (CPDF) which characterizes the probability density of finding an object (e.g., a particle in a fluid) to certain distance of other, with each of these two having a nearest neighbor to a…

Statistical Mechanics · Physics 2015-03-19 René D. Rohrmann , Ernesto Zurbriggen

The use of exactly-solvable Richardson-Gaudin (R-G) models to describe the physics of systems with strong pair correlations is reviewed. We begin with a brief discussion of Richardson's early work, which demonstrated the exact solvability…

Nuclear Theory · Physics 2008-11-26 J. Dukelsky , S. Pittel , G. Sierra

A Borromean nucleus is a bound three-body system which is pairwise unbound because none of the two-body subsystem interactions are strong enough to bind them in pairs. As a consequence, the single-particle spectrum of a neutron in the core…

Nuclear Theory · Physics 2017-01-30 R. M. Id Betan

Modeling of biomolecular systems plays an essential role in understanding biological processes, such as ionic flow across channels, protein modification or interaction, and cell signaling. The continuum model described by the…

Biological Physics · Physics 2015-12-08 Yu Qiao , Benzhuo Lu

We derive the approximate solution for the pairing Hamiltonian in the Berggren ensemble of single particle states including bound, resonance and non-resonant scattering states. We show that this solution is reliable in the limit of a weak…

Nuclear Theory · Physics 2016-04-20 A. Mercenne , N. Michel , M. Ploszajczak

There has been increasing interest in studying the Richardson model from which one can derive the exact solution for certain pairing Hamiltonians. However, it is still a numerical challenge to solve the nonlinear equations involved. In this…

Nuclear Theory · Physics 2016-03-25 Chong Qi , Tao Chen

We compute singlet pairing gaps and critical temperatures in pure neutron matter with different many-body approximations. Medium effects tend to reduce gaps and critical temperatures compared to the standard BCS ansatz. In the mean-field…

Nuclear Theory · Physics 2022-06-01 M. Drissi , A. Rios

Nuclear level density is calculated with the combinatorial method based on the relativistic density functional theory including pairing correlations. The Strutinsky method is adopted to smooth the total state density in order to refine the…

Nuclear Theory · Physics 2024-01-18 Xiao-Fei Jiang , Xin-Hui Wu , Peng-Wei Zhao , Jie Meng

Fermion systems with more than two components can exhibit pairing condensates of much more complex structure than the well-known single BCS condensate of spin-up and spin-down fermions. In the framework of the exactly solvable SO(8)…

Mathematical Physics · Physics 2015-05-14 G. F. Bertsch , J. Dukelsky , B. Errea , C. Esebbag