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arXiv · 1612.06805

Search for $α$-cluster states in even-even Cr isotopes

M. A. Souza·H. Miyake
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Abstract

The $α+ \mathrm{core}$ structure is investigated in even-even Cr isotopes from the viewpoint of the local potential model. The comparison of $Q_α/A$ values for even-even Cr isotopes and even-even $A = 46,54,56,58$ isobars indicates that $^{46}$Cr and $^{54}$Cr are the most favorable even-even Cr isotopes for $α$-clustering. The ground state bands of the two Cr isotopes are calculated through a local $α+ \mathrm{core}$ potential with two variable parameters. The calculated spectra give a very good description of most experimental $^{46}$Cr and $^{54}$Cr levels. The reduced $α$-widths, rms intercluster separations and $B(E2)$ transition rates are determined for the ground state bands. The calculations reproduce the order of magnitude of the available experimental $B(E2)$ values without using effective charges and indicate that the first members of the ground state bands present a stronger $α$-cluster character. The volume integral per nucleon pair and rms radius obtained for the $α+^{50}$Ti potential are consistent with those reported previously in the analysis of $α$ elastic scattering on $^{50}$Ti.

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M. A. Souza, H. Miyake. 2017-02-26. Search for $α$-cluster states in even-even Cr isotopes. https://doi.org/10.1140/epja%2Fi2017-12339-9

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