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Title: Two-body random ensemble in nuclei

Abstract

Combining analytical and numerical methods, we investigate properties of the two-body random ensemble (TBRE). We compare the TBRE with the Gaussian orthogonal ensemble of random matrices. Using the geometric properties of the nuclear shell model, we discuss the information content of nuclear spectra and gain insight in the difficulties encountered when fitting the effective interaction. We exhibit the existence of correlations between spectral widths pertaining to different quantum numbers. Using these results, we deduce the preponderance of zero-spin ground states in the TBRE. We demonstrate the existence of correlations between spectra with different quantum numbers and/or in different nuclei.

Authors:
 [1];  [2];  [3]
  1. Department of Physics and Astronomy, University of Tennessee, Knoxville, Tennessee 37996 (United States)
  2. (United States)
  3. Max-Planck Institut fuer Kernphysik, D-69029 Heidelberg (Germany)
Publication Date:
OSTI Identifier:
20771189
Resource Type:
Journal Article
Resource Relation:
Journal Name: Physical Review. C, Nuclear Physics; Journal Volume: 73; Journal Issue: 1; Other Information: DOI: 10.1103/PhysRevC.73.014311; (c) 2006 The American Physical Society; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
73 NUCLEAR PHYSICS AND RADIATION PHYSICS; COMPARATIVE EVALUATIONS; CORRELATIONS; GROUND STATES; MATRICES; NUCLEI; QUANTUM NUMBERS; RANDOMNESS; SHELL MODELS; SPECTROSCOPIC FACTORS; SPIN; STATISTICAL MODELS; TWO-BODY PROBLEM

Citation Formats

Papenbrock, T., Physics Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, and Weidenmueller, H. A.. Two-body random ensemble in nuclei. United States: N. p., 2006. Web. doi:10.1103/PhysRevC.73.014311.
Papenbrock, T., Physics Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, & Weidenmueller, H. A.. Two-body random ensemble in nuclei. United States. doi:10.1103/PhysRevC.73.014311.
Papenbrock, T., Physics Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, and Weidenmueller, H. A.. Sun . "Two-body random ensemble in nuclei". United States. doi:10.1103/PhysRevC.73.014311.
@article{osti_20771189,
title = {Two-body random ensemble in nuclei},
author = {Papenbrock, T. and Physics Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831 and Weidenmueller, H. A.},
abstractNote = {Combining analytical and numerical methods, we investigate properties of the two-body random ensemble (TBRE). We compare the TBRE with the Gaussian orthogonal ensemble of random matrices. Using the geometric properties of the nuclear shell model, we discuss the information content of nuclear spectra and gain insight in the difficulties encountered when fitting the effective interaction. We exhibit the existence of correlations between spectral widths pertaining to different quantum numbers. Using these results, we deduce the preponderance of zero-spin ground states in the TBRE. We demonstrate the existence of correlations between spectra with different quantum numbers and/or in different nuclei.},
doi = {10.1103/PhysRevC.73.014311},
journal = {Physical Review. C, Nuclear Physics},
number = 1,
volume = 73,
place = {United States},
year = {Sun Jan 15 00:00:00 EST 2006},
month = {Sun Jan 15 00:00:00 EST 2006}
}
  • We conduct a systematic investigation of the nuclear collective dynamics that emerges in systems with two-body random interactions. We explore the development of the mean field and study its geometry. We investigate multipole collectivities in the many-body spectra and their dependence on the underlying two-body interaction Hamiltonian. The quadrupole-quadrupole interaction component appears to be dynamically dominating in the two-body random ensemble. This quadrupole coherence leads to rotational spectral features and thus suggests the formation of the deformed mean-field of a specific geometry.
  • Cited by 3
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