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Related papers: Parity-Projected Shell Model Monte Carlo Level Den…

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We present a new combinatorial method for the calculation of the nuclear level density. It is based on a Monte Carlo technique, in order to avoid a direct counting procedure which is generally impracticable for high-A nuclei. The Monte…

Nuclear Theory · Physics 2008-11-26 N. Cerf

The electromagnetic and weak neutral current matrix elements that enter in the analysis of parity-violating quasielastic electron scattering are calculated using a continuum nuclear shell model. New approximations to the on-shell…

Nuclear Theory · Physics 2008-11-26 J. E. Amaro , J. A. Caballero , T. W. Donnelly , A. M. Lallena , E. Moya de Guerra , J. M. Udias

The structures of odd-odd $N=Z$ nuclei in the lower \emph{fp} shell have been investigated with a new isospin-nonconserving microscopical interaction. The interaction is derived from a high-precision charge-dependent Bonn nucleon-nucleon…

Nuclear Theory · Physics 2008-11-26 C. Qi , F. R. Xu

Pair transfer is a unique tool to study pairing correlations in nuclei. Neutron-proton pairing is investigated in the N=Z nuclei of the f-shell, through the reaction (p,3He) in inverse kinematics, that allows to populate at the same time…

Nuclear Experiment · Physics 2024-10-21 M. Assié , H. Jacob , Y. Blumenfeld , V. Girard-Alcindor

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

Weak interaction rates and the associated energy losses for massive nuclei in the fp-shell are calculated in stellar matter using a modified form of proton-neutron quasiparticle RPA model with separable Gamow-Teller forces. A total of 209…

Nuclear Theory · Physics 2007-05-23 J. -U. Nabi , H. V. Klapdor-Kleingrothaus

The knowledge of the nuclear level density is necessary for understanding various reactions including those in the stellar environment. Usually the combinatorics of Fermi-gas plus pairing is used for finding the level density. Recently a…

Nuclear Theory · Physics 2016-06-22 Roman Sen'kov , Vladimir Zelevinsky

We show that the neutron and proton transition densities predicted by recent quantum Monte Carlo calculations for A=6,7 nuclei are consistent with pion scattering from 6Li and 7Li at energies near the Delta resonance. This has provided a…

Nuclear Theory · Physics 2008-11-26 T. -S. H. Lee , R. B. Wiringa

Level densities have been extracted from primary gamma spectra for 56,57-Fe and 96,97-Mo nuclei using (3-He,alpha gamma) and (3-He,3-He') reactions on 57-Fe and 97-Mo targets. The level density curves reveal step structures above the…

We report on the development of a new shell-model Monte Carlo algorithm which uses the proton-neutron formalism. Shell model Monte Carlo methods, within the isospin formulation, have been successfully used in large-scale shell-model…

Nuclear Theory · Physics 2015-06-26 C. Ozen , D. J. Dean

The heat capacity of iron isotopes is calculated within the interacting shell model using the complete $(pf+0g_{9/2})$-shell. We identify a signature of the pairing transition in the heat capacity that is correlated with the suppression of…

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

We investigate the degree of $\alpha$ ($^4$He nucleus) clustering in the ground-state density profiles of $^{44}$Ti and $^{52}$Ti. Two types of density distributions, shell- and cluster-model configurations, are generated fully…

Nuclear Theory · Physics 2022-11-09 W. Horiuchi , N. Itagaki

We study theoretically the electric dipole transitions of even Ni isotopes at low energies, using the self-consistent quasi-particle random-phase approximation (RPA) with the D1S Gogny interaction and a continuum-RPA model with the SLy4…

Nuclear Theory · Physics 2015-10-28 P. Papakonstantinou , H. Hergert , R. Roth

We calculate the parity-dependent level density ratios for $^{240,242}$Pu across a broad range of quadrupole deformations, from the spherical configuration up to the superdeformed region, explicitly including both the ground-state minimum…

Nuclear Theory · Physics 2026-01-29 A. Rahmatinejad , T. M. Shneidman , N. Jovancevic

We perform Shell Model Monte Carlo calculations of selected N=Z pf-shell nuclei with a schematic hamiltonian containing isovector pairing and quadrupole-quadrupole interactions. Compared to realistic interactions, this hamiltonian does not…

Nuclear Theory · Physics 2009-10-30 K. Langanke , P. Vogel , Dao-Chen Zheng

Experimentally observed heaviest $N \approx Z$ nuclei, Ru isotopes, are investigated by the shell model on a spherical basis with the extended $P+QQ$ Hamiltonian. The energy levels of all the Ru isotopes can be explained by the shell model…

Nuclear Theory · Physics 2009-11-10 M. Hasegawa , K. Kaneko , T. Mizusaki , S. Tazaki

Novel equations for the electric dipole polarizability $\alpha_{_{E1}}$ of low-lying excited states in atomic nuclei -- and the related $(-2)$ moment of the total photo-absorption cross section, $\sigma_{_{-2}}$ -- are inferred in terms of…

Nuclear Theory · Physics 2024-03-12 José Nicolás Orce , Cebo Ngwetsheni

We investigate the nature and impact of shell effects on nuclear level density (NLD) and particle emission probability as a function of temperature in a microscopic theoretical framework of Statistical Model for nuclei ranging from neutron…

Nuclear Theory · Physics 2023-03-03 Mamta Aggarwal

Level density $\rho$ is derived for a finite system with strongly interacting nucleons at a given energy E, neutron N and proton Z particle numbers, projection of the angular momentum M, and other integrals of motion, within the…

Nuclear Theory · Physics 2023-08-22 A. G. Magner , A. I. Sanzhur , S. N. Fedotkin , A. I. Levon , U. V. Grygoriev , S. Shlomo

Monopole shift in the proton states in odd neutron rich F isotopes has been studied with neutron number changing from N = 10 to 20 for three different interactions. The variation of monopole shift point out towards appearance of shell…

Nuclear Theory · Physics 2011-05-12 P. C. Srivastava , I. Mehrotra