Band structures in ${}^{106}$Pd

The high spin states of ${}^{106}$Pd have been investigated with in-beam $\gamma$-ray spectroscopic methods using the ${}^{100}$Mo(${}^{11}\text{B},1p4n$)${}^{106}$Pd reaction at a beam energy of 60 MeV. All earlier known bands were extended considerably and additional bands were identified. The configurations of these bands are discussed on the basis of the experimental aligned angular momenta and total Routhian surface calculations. Both two-quasineutron and two-quasiproton structures have been found in ${}^{106}$Pd. The nonyrast low-lying positive-parity band was interpreted as a $\gamma$-vibrational band.

Figure 1

Deduced new level scheme of ${}^{106}$Pd from the present experiment. The $\gamma$ energies are in keV. The widths of the arrows are proportional to the intensities of the transitions.

Figure 2

Sample spectra gated by 732, 1168, and 960 keV. Peaks without any symbols belong to ${}^{106}$Pd. The energies marked by the closed circle, semicircles, heart symbols, triangles, and diamonds are contaminants from ${}^{105}$Ag, ${}^{106}$Ag, ${}^{107}$Ag, ${}^{105}$Pd, and ${}^{107}$Pd, respectively.

Figure 3

Experimental alignment as a function of rotational frequency $\omega$ for bands 1 and 2 in ${}^{106}$Pd.

Figure 4

Empirical E-GOS plot for bands 1 and 2 in ${}^{106}$Pd.

Figure 5

Experimentally observed odd-even spin energy staggering in band 5 together with the values of the quasi-$\gamma$ band in ${}^{104}$Ru.

Figure 6

Polar coordinate plots of TRS for ${}^{106}$Pd. Contour lines are in 200-keV increments. (a) Vacuum: $\hslash \omega =0.0$ MeV, with a minimum at ${\beta }_2=0.175$, ${\beta }_4=-0.003$, $\gamma =1.{314}^{\circ }.$ (b) $\nu h_{11/2}\otimes g_{7/2}/d_{5/2}$: $\hslash \omega =0.25$ MeV, with a minimum at ${\beta }_2=0.189$, ${\beta }_4=-0.003$, $\gamma =7.{228}^{\circ }.$

Figure 7

Experimental alignments of bands 3 and 4 in ${}^{106}$Pd.