High-spin structure and Band Termination in $^{103}$Cd

TL;DR

This study investigates the high-spin states and band termination in the neutron-deficient nucleus $^{103}$Cd using in-beam gamma-ray spectroscopy, revealing shape changes and band termination phenomena up to high angular momentum.

Contribution

The paper extends the known level scheme of $^{103}$Cd and provides the first detailed experimental and theoretical analysis of shape transition and band termination at high spin.

Findings

Positive parity levels extended up to 7.071 MeV and J=35/2.

Negative parity sequence terminates at J=47/2 and 11.877 MeV.

Evidence for shape change from prolate to oblate above J=39/2.

Abstract

Excited states of the neutron deficient $^{103}$Cd nucleus have been investigated via the $^{72}$Ge($^{35}$Cl, p3n) reaction at beam energy of 135 MeV by use of in-beam spectroscopic methods. Gamma rays depopulating the excited states were detected using the Gammasphere spectrometer with high-fold $\gamma$-ray coincidences. A quadrupole $\gamma$-ray coincidence analysis ($\gamma^{4}$) has been used to extend the known level scheme. The positive parity levels have been established up to $J = 35/2\hbar$ and $E_{x} = 7.071$ MeV. In addition to the observation of highly-fragmented level scheme belonging to the positive-parity sequences at E$_{x}\sim$ 5 MeV, the termination of a negative-parity sequence connected by $E2$ transitions has been established at $J = 47/2 \hbar$ and $E_{x} = 11.877$ MeV. The experimental results corresponding to both the positive- and negative-parity sequences have been theoretically interpreted in the framework of the core particle coupling model. Evidence is presented for a shape change from collective prolate to non-collective oblate above the $J^{\pi} = 39/2^{-}$ (8011 keV) level and for a smooth termination of the negative-parity band.