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Spectroscopy with random and displaced random ensembles

V. Velázquez·A. P. Zuker
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Abstract

Due to the time reversal invariance of the angular momentum operator J^2, the average energies and variances at fixed J for random two-body Hamiltonians exhibit odd-even-J staggering, that may be especially strong for J=0. It is shown that upon ensemble averaging over random runs, this behaviour is reflected in the yrast states. Displaced (attractive) random ensembles lead to rotational spectra with strongly enhanced BE2 transitions for a certain class of model spaces. It is explained how to generalize these results to other forms of collectivity.

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V. Velázquez, A. P. Zuker. 2002-02-23. Spectroscopy with random and displaced random ensembles. https://doi.org/10.1103/physrevlett.88.072502

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