The anomalous quadrupole collectivity in Te isotopes

TL;DR

This paper uses large-scale shell model calculations to explain the unique quadrupole collectivity and transition behaviors in Te isotopes, revealing the role of neutron-proton correlations near N=50.

Contribution

It provides a detailed shell model analysis that reproduces the anomalous transition patterns and explains their origin in neutron-proton correlations.

Findings

Reproduces equally-spaced yrast spectra in Te isotopes.

Shows constant B(E2) values in $^{114}$Te.

Identifies contrasting B(E2) behaviors in light and heavy isotopes.

Abstract

We present systematic calculations on the spectroscopy and transition properties of even-even Te isotopes by using the large-scale configuration interaction shell model approach with a realistic interaction. These nuclei are of particular interest since their yrast spectra show a vibrational-like equally-spaced pattern but the few known E2 transitions show anomalous rotational-like behavior, which cannot be reproduced by collective models. Our calculations reproduce well the equally-spaced spectra of those isotopes as well as the constant behavior of the $B(E2)$ values in $^{114}$Te. The calculated $B(E2)$ values for neutron-deficient and heavier Te isotopes show contrasting different behaviors along the yrast line. The $B(E2)$ of light isotopes can exhibit a nearly constant bevavior upto high spins. We show that this is related to the enhanced neutron-proton correlation when approaching $N=50$.