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

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 نشر من قبل Umesh Garg
 تاريخ النشر 2007
  مجال البحث
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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 $J = 35/2hbar$ 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.

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