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Title: Coupled-Cluster and Configuration-Interaction Calculations for Heavy Nuclei

Abstract

We compare coupled-cluster (CC) and configuration-interaction (CI) results for {sup 56}Ni obtained in the pf-shell basis, focusing on practical CC approximations that can be applied to systems with dozens or hundreds of correlated fermions. The weight of the reference state and the strength of correlation effects are controlled by the gap between the f{sub 7/2} orbit and the f{sub 5/2}, p{sub 3/2}, p{sub 1/2} orbits. Independent of the gap, the CC method with 1p-1h and 2p-2h clusters and a noniterative treatment of 3p-3h clusters is as accurate as the more demanding CI approach truncated at the 4p-4h level.

Authors:
 [1]; ; ;  [2];  [3];  [2];  [4]
  1. Department of Physics, Central Michigan University, Mount Pleasant, Michigan 48859 (United States)
  2. Department of Chemistry, Michigan State University, East Lansing, Michigan 48824 (United States)
  3. Department of Physics and Astronomy and National Superconducting Cyclotron Laboratory, Michigan State University, East Lansing, Michigan 48824 (United States)
  4. (United States)
Publication Date:
OSTI Identifier:
20957748
Resource Type:
Journal Article
Resource Relation:
Journal Name: Physical Review Letters; Journal Volume: 98; Journal Issue: 11; Other Information: DOI: 10.1103/PhysRevLett.98.112501; (c) 2007 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; APPROXIMATIONS; CLUSTER MODEL; COMPARATIVE EVALUATIONS; CONFIGURATION INTERACTION; FERMIONS; HEAVY NUCLEI; NICKEL 56; SHELL MODELS

Citation Formats

Horoi, M., Gour, J. R., Wloch, M., Lodriguito, M. D., Brown, B. A., Piecuch, P., and Department of Physics and Astronomy and National Superconducting Cyclotron Laboratory, Michigan State University, East Lansing, Michigan 48824. Coupled-Cluster and Configuration-Interaction Calculations for Heavy Nuclei. United States: N. p., 2007. Web. doi:10.1103/PHYSREVLETT.98.112501.
Horoi, M., Gour, J. R., Wloch, M., Lodriguito, M. D., Brown, B. A., Piecuch, P., & Department of Physics and Astronomy and National Superconducting Cyclotron Laboratory, Michigan State University, East Lansing, Michigan 48824. Coupled-Cluster and Configuration-Interaction Calculations for Heavy Nuclei. United States. doi:10.1103/PHYSREVLETT.98.112501.
Horoi, M., Gour, J. R., Wloch, M., Lodriguito, M. D., Brown, B. A., Piecuch, P., and Department of Physics and Astronomy and National Superconducting Cyclotron Laboratory, Michigan State University, East Lansing, Michigan 48824. Fri . "Coupled-Cluster and Configuration-Interaction Calculations for Heavy Nuclei". United States. doi:10.1103/PHYSREVLETT.98.112501.
@article{osti_20957748,
title = {Coupled-Cluster and Configuration-Interaction Calculations for Heavy Nuclei},
author = {Horoi, M. and Gour, J. R. and Wloch, M. and Lodriguito, M. D. and Brown, B. A. and Piecuch, P. and Department of Physics and Astronomy and National Superconducting Cyclotron Laboratory, Michigan State University, East Lansing, Michigan 48824},
abstractNote = {We compare coupled-cluster (CC) and configuration-interaction (CI) results for {sup 56}Ni obtained in the pf-shell basis, focusing on practical CC approximations that can be applied to systems with dozens or hundreds of correlated fermions. The weight of the reference state and the strength of correlation effects are controlled by the gap between the f{sub 7/2} orbit and the f{sub 5/2}, p{sub 3/2}, p{sub 1/2} orbits. Independent of the gap, the CC method with 1p-1h and 2p-2h clusters and a noniterative treatment of 3p-3h clusters is as accurate as the more demanding CI approach truncated at the 4p-4h level.},
doi = {10.1103/PHYSREVLETT.98.112501},
journal = {Physical Review Letters},
number = 11,
volume = 98,
place = {United States},
year = {Fri Mar 16 00:00:00 EDT 2007},
month = {Fri Mar 16 00:00:00 EDT 2007}
}
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