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arXiv · 1003.3624

Nuclear Structure in the Framework of the Unitary Correlation Operator Method

Robert Roth·Thomas Neff·Hans Feldmeier
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Abstract

Correlations play a crucial role in the nuclear many-body problem. We give an overview of recent developments in nuclear structure theory aiming at the description of these interaction-induced correlations by unitary transformations. We focus on the Unitary Correlation Operator Method (UCOM), which offers a very intuitive, universal and robust approach for the treatment of short-range correlations. We discuss the UCOM formalism in detail and highlight the connections to other methods for the description of short-range correlations and the construction of effective interactions. In particular, we juxtapose UCOM with the Similarity Renormalization Group (SRG) approach, which implements the unitary transformation of the Hamiltonian through a very flexible flow-equation formulation. The UCOM- and SRG-transformed interactions are compared on the level of matrix elements and in many-body calculations within the no-core shell model and with Hartree-Fock plus perturbation theory for a variety of nuclei and observables. These calculations provide a detailed picture of the similarities and differences as well as the advantages and limitations of unitary transformation methods.

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Robert Roth, Thomas Neff, Hans Feldmeier. 2010-03-15. Nuclear Structure in the Framework of the Unitary Correlation Operator Method. https://doi.org/10.1016/j.ppnp.2010.02.003

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