We report new data from a ${}^{150}\mathrm{Nd}(p,t){}^{148}\mathrm{Nd}$ experiment performed at the John D. Fox Accelerator Laboratory of Florida State University. In total, 54 excited states of ${}^{148}\mathrm{Nd}$ were observed up to an excitation energy of 3500 keV. In this work, we focus on $0^{+}$ states and their band members. In contrast to previous work, the $0_3^{+}$ band is proposed as the candidate for the two-phonon octupole vibrational band. Supporting $spdf$ IBM-1 calculations are presented. To test the robustness of the IBM calculations, several observables were interrogated and are discussed in this publication. In addition, we make the case that neither the $0_2^{+}$ nor the $0_3^{+}$ states of the other $N=88$ isotones are likely good candidates for two-phonon octupole states. Based on our new data for ${}^{148}\mathrm{Nd}$, we propose candidates in ${}^{150}\mathrm{Sm}$ and ${}^{152}\mathrm{Gd}$. Using available $\gamma$-decay data for states with moderate spins in the yrast sequence and a comparison to IBM calculations, we also show how the staggering of the $B\left(E1\right)/B\left(E2\right)$ ratios in the yrast sequence can possibly be used to probe the appearance of bands with multiple octupole phonons.

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• Collective levels
• Direct reactions
• Electromagnetic transitions
• Energy levels
• Nuclear reactions
• Nuclear structure & decays
• Nuclear transition rates
• Transfer reactions
• 90 ≤ A ≤ 149
• Collective models