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Related papers: Moments Method for Shell-Model Level Density

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A new model for calculating nuclear level densities is investigated. The single-nucleon spectra are calculated in a relativistic mean-field model with energy-dependent effective mass, which yields a realistic density of single-particle…

Nuclear Theory · Physics 2008-11-26 R. Pezer , A. Ventura , D. Vretenar

A new high-performance algorithm for calculating the spin- and parity-dependent shell model nuclear level densities using methods of statistical spectroscopy in the proton-neutron formalism was recently proposed. When used in valence spaces…

Nuclear Theory · Physics 2011-08-17 R. A. Sen'kov , M. Horoi , V. G. Zelevinsky

Levels densities of independent-particle Hamiltonians can be calculated easily by using the real-time representation of the evolution operator together with the fast Fourier transform. We describe the method and implement it with a set of…

Nuclear Theory · Physics 2015-06-18 G. F. Bertsch , L. M. Robledo

Total and parity-projected level densities of iron-region nuclei are calculated microscopically by using Monte Carlo methods for the nuclear shell model in the complete $(pf+0g_{9/2})$-shell. The calculated total level density is found to…

Nuclear Theory · Physics 2007-05-23 H. Nakada , Y. Alhassid

We use quantum Monte Carlo methods in the framework of the interacting nuclear shell model to calculate the statistical properties of nuclei at finite temperature and/or excitation energies. With this approach we can carry out realistic…

Nuclear Theory · Physics 2009-11-11 Y. Alhassid

We introduce spin projection methods in the shell model Monte Carlo approach and apply them to calculate the spin distribution of level densities for iron-region nuclei using the complete $(pf+g_{9/2})$-shell. We compare the calculated…

Nuclear Theory · Physics 2008-11-26 Y. Alhassid , S. Liu , H. Nakada

A particle-number reprojection method is applied in the framework of the shell model Monte Carlo approach to calculate level densities for a family of nuclei using Monte Carlo sampling for a single nucleus. In particular we can also…

Nuclear Theory · Physics 2009-11-06 S. Liu , Y. Alhassid , H. Nakada

Conventional diagonalization methods to calculate nuclear energy levels in the framework of the configuration-interaction (CI) shell model approach are prohibited in very large model spaces. The shell model Monte Carlo (SMMC) is a powerful…

Nuclear Theory · Physics 2025-01-08 Y. Alhassid , M. Bonett-Matiz , C. N. Gilbreth , S. Vartak

We calculate microscopically total and parity-projected level densities for $\beta$-stable even-even nuclei between Fe and Ge, using the shell model Monte Carlo methods in the complete $(pf+0g_{9/2})$-shell. A single-particle level density…

Nuclear Theory · Physics 2009-10-31 H. Nakada , Y. Alhassid

We systematically study the nuclear level densities of superheavy nuclei, including odd systems, using the single-particle energies obtained with the Woods-Saxon potential diagonalization. Minimization over many deformation parameters for…

A microscopic method for calculating nuclear level densities (NLD) is developed, based on the framework of energy density functionals. Intrinsic level densities are computed from single-quasiparticle spectra obtained in a finite-temperature…

Nuclear Theory · Physics 2020-11-18 Jie Zhao , Tamara Nikšić , Dario Vretenar

In the independent-particle model, the nuclear level density is determined from the neutron and proton single-particle level densities. The single-particle level density for the positive-energy continuum levels is important at high…

Nuclear Theory · Physics 2009-11-10 R. J. Charity , L. G. Sobotka

The main formalisms of partial level densities (PLD) used in preequilibrium nuclear reaction models, based on the equidistant spacing model (ESM), are considered. A collection of FORTRAN77 functions for PLD calculation by using 14…

Computational Physics · Physics 2009-10-31 M. Avrigeanu , V. Avrigeanu

We describe the use of the Density Matrix Renormalization Group method as a means of approximately solving large-scale nuclear shell-model problems. We focus on an angular-momentum-conserving variant of the method and report test results…

Nuclear Theory · Physics 2011-05-12 S. Pittel , N. Sandulescu

The feasibility of shell-model calculations is radically extended by the Quantum Monte Carlo Diagonalization method with various essential improvements. The major improvements are made in the sampling for the generation of shell-model basis…

Nuclear Theory · Physics 2008-11-26 Michio Honma , Takahiro Mizusaki , Takaharu Otsuka

Level density $\rho(E,N,Z)$ is derived for a nuclear system with a given energy $E$, neutron $N$, and proton $Z$ particle numbers, within the semiclassical extended Thomas-Fermi and periodic-orbit theory beyond the Fermi-gas saddle-point…

Nuclear Theory · Physics 2021-12-06 A. G. Magner , A. I. Sanzhur , S. N. Fedotkin , A. I. Levon , S. Shlomo

The prediction of cross sections for nuclei far off stability is crucial in the field of nuclear astrophysics. In recent calculations the nuclear level density -- as an important ingredient to the statistical model (Hauser-Feshbach) -- has…

Astrophysics · Physics 2016-08-30 T. Rauscher , F. -K. Thielemann , K. -L. Kratz

The configuration interaction approach to nuclear structure uses the effective Hamiltonian in a finite orbital space. The various parts of this Hamiltonian and their interplay are responsible for specific features of physics including the…

Nuclear Theory · Physics 2017-02-27 S. Karampagia , Vladimir Zelevinsky

A new method for calculation of shell model intrinsic density matrices, defined as two-particle density matrices integrated over the centre-of-mass position vector of two last particles and complemented with isospin variables, has been…

Nuclear Theory · Physics 2007-05-23 A. Deveikis , G. Kamuntavicius

New developments have been brought to our energy-, spin- and parity-dependent nuclear level densities based on the microscopic combinatorial method. Our new calculation is based on the BSkG3 mean-field model which relies on a…

Nuclear Theory · Physics 2026-01-08 S. Goriely , W. Ryssens , S. Hilaire , A. J. Koning