skip to main content
OSTI.GOV title logo U.S. Department of Energy
Office of Scientific and Technical Information

Title: Shell model description of band structure in 48Cr

Abstract

The band structure for normal and abnormal parity bands in 48Cr are described using the m-scheme shell model. In addition to full fp-shell, two particles in the 1d3/2 orbital are allowed in order to describe intruder states. The interaction includes fp-, sd- and mixed matrix elements.

Authors:
 [1];  [2]
  1. Facultad de Fisica e Inteligencia Artificial, Universidad Veracruzana, Sebastian Camacho 5, Centro, CP 91000, Xalapa, Ver. (Mexico)
  2. Facultad de Ciencias, Universidad Nacional Autonoma de Mexico (Mexico)
Publication Date:
OSTI Identifier:
21054859
Resource Type:
Journal Article
Resource Relation:
Journal Name: AIP Conference Proceedings; Journal Volume: 884; Journal Issue: 1; Conference: 6. Latin American symposium on nuclear physics and applications, Iguazu (Argentina), 3-7 Oct 2005; Other Information: DOI: 10.1063/1.2710621; (c) 2007 American Institute of Physics; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
73 NUCLEAR PHYSICS AND RADIATION PHYSICS; CHROMIUM 48; ENERGY LEVELS; MATRIX ELEMENTS; NUCLEAR STRUCTURE; PARITY; SHELL MODELS

Citation Formats

Vargas, Carlos E., and Velazquez, Victor M. Shell model description of band structure in 48Cr. United States: N. p., 2007. Web. doi:10.1063/1.2710621.
Vargas, Carlos E., & Velazquez, Victor M. Shell model description of band structure in 48Cr. United States. doi:10.1063/1.2710621.
Vargas, Carlos E., and Velazquez, Victor M. Mon . "Shell model description of band structure in 48Cr". United States. doi:10.1063/1.2710621.
@article{osti_21054859,
title = {Shell model description of band structure in 48Cr},
author = {Vargas, Carlos E. and Velazquez, Victor M.},
abstractNote = {The band structure for normal and abnormal parity bands in 48Cr are described using the m-scheme shell model. In addition to full fp-shell, two particles in the 1d3/2 orbital are allowed in order to describe intruder states. The interaction includes fp-, sd- and mixed matrix elements.},
doi = {10.1063/1.2710621},
journal = {AIP Conference Proceedings},
number = 1,
volume = 884,
place = {United States},
year = {Mon Feb 12 00:00:00 EST 2007},
month = {Mon Feb 12 00:00:00 EST 2007}
}
  • We study nuclear high-spin states undergoing the transition to the fully stretched configuration with maximum angular momentum I{sub max} within the space of valence nucleons. To this end, we perform a systematic theoretical analysis of non-fully-stretched I{sub max}-2 and I{sub max}-1 f{sub 7/2}{sup n} seniority isomers and d{sub 3/2}{sup -1}f{sub 7/2}{sup n + 1} intruder states in the A{approx}44 nuclei from the lower-fp shell. We employ two theoretical approaches: (i) the density functional theory based on the cranked self-consistent Skyrme-Hartree-Fock method, and (ii) the nuclear shell model in the full sdfp configuration space allowing for 1p-1h cross-shell excitations. We emphasizemore » the importance of restoration of broken angular momentum symmetry inherently obscuring the mean-field treatment of high-spin states. Overall good agreement with experimental data is obtained.« less
  • Large scale shell model calculations in the valence space spanned by two major oscillator shells (sd and pf) describe simultaneously the superdeformed excited band of {sup 36}Ar and its spherical ground state. We explain the appearance of this superdeformed band at low excitation energy as a consequence of the very large quadrupole correlation energy of the configurations with many particles and many holes (np-nh) relative to the normal filling of the spherical mean field orbits (0p-0h). We study the mechanism of mixing between the different configurations to understand why the superdeformed band survives and how it finally decays into themore » low-lying spherical states via the indirect mixing of the 0p-0h and 4p-4h configurations.« less
  • We study nuclear high-spin states undergoing the transition to the fully stretched configuration with maximum angular momentum I{sub max} within the space of valence nucleons. To this end, we perform a systematic theoretical analysis of non-fully-stretched I{sub max}-2 and I{sub max}-1 f{sub 7/2}{sup n} seniority isomers and d{sub 3/2}{sup -1}f{sub 7/2}{sup n+1} intruder states in the A{approx}44 nuclei from the lower-fp shell. We employ two theoretical approaches: (i) the density functional theory based on the cranked self-consistent Skyrme-Hartree-Fock method, and (ii) the nuclear shell model in the full sdfp configuration space allowing for 1p-1h cross-shell excitations. We emphasize the importancemore » of restoration of broken angular momentum symmetry inherently obscuring the mean-field treatment of high-spin states. Overall good agreement with experimental data is obtained.« less
  • An effective fermion interaction of maximum particle rank four, comprised of operators which form the integrity basis of an SU(3)..-->..R(3) algebra, has been found sufficient to reproduce almost exactly, within a single leading irreducible representation of pseudo SU(3), the ground- and gamma-band rotational structure as well as the concomitant interband and intraband B(E2) strengths of states in the strongly deformed nuclei. Results are given for /sup 164/Er.
  • A shell-model theory, called the pseudo SU(3) model, which was proposed previously for giving the structure of low-lying states in heavy deformed nuclei is used to predict the number of 1/sup +/ states with strong M1 transitions to ground states for the nuclei /sup 154/Sm, /sup 156//sup --//sup 160/Gd, /sup 164/Dy, /sup 168/Er, /sup 174/Yb of the rare earth region and the actinide species /sup 232/Th, /sup 234//sup --//sup 240/U, /sup 242/Pu. Results are also given for E2 and M3 transition strengths in these nuclei. The measures provide a rigorous test of the theory, which in reality is a many-particlemore » Nilsson scheme, because the real M1, E2, and M3 operators are used in the calculations. It is found that the results for E2 strengths using the real quadrupole operator Q-script differ by less than 5 from those of calculations that use the operator Q-italic-tilde which is a generator of the pseudo SU(3) symmetry. This is so even for weak interband transitions. To further test the theory additional experimental information on the 2/sup +//sub ..gamma../ states is necessary. In particular, the 1/sup +/ ..-->.. 2/sup +//sub ..gamma../ decay strengths are needed to differentiate between theories for the structure of the giant M1 states. copyright 1987 Academic Press, Inc.« less