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Examining the wobbling interpretation of low-lying bands in $gamma$-soft nuclei within the interacting boson-fermion model

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 نشر من قبل Kosuke Nomura
 تاريخ النشر 2021
  مجال البحث
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The interpretation of the recently reported low-lying excited bands in $gamma$-soft odd-mass nuclei as wobbling bands is examined in terms of the interacting boson-fermion model that is based on the universal nuclear energy density functional. The predicted mixing ratios of the $Delta{I}=1$ electric quadrupole ($E2$) to magnetic dipole ($M1$) transition rates between yrast bands and those yrare bands previously interpreted as wobbling bands in $^{135}$Pr, $^{133}$La, $^{127}$Xe, and $^{105}$Pd nuclei are consistently smaller in magnitude than the experimental values on which the wobbling interpretation is based. These calculated mixing ratios indicate the predominant $M1$ character of the transitions from the yrare bands under consideration to the yrast bands, being in agreement with the new experimental data, which involve both the angular distribution and linear polarization measurements. The earlier wobbling assignments are severely questioned.



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