We have studied the level structure of ${}_{}{}^{173}{}_{}{}^{}\mathrm{Yb}$ via the ${}_{}{}^{172}{}_{}{}^{}\mathrm{Yb}(d,p){}_{}{}^{173}{}_{}{}^{}\mathrm{Yb}$ and ${}_{}{}^{174}{}_{}{}^{}\mathrm{Yb}(d,t){}_{}{}^{173}{}_{}{}^{}\mathrm{Yb}$ reactions. We measured the excitation energies of 96 states up to 2.63 MeV, including all but two of the adopted levels. 55 of the states were not previously reported. We took angular distributions on each reaction and analyzed them with distorted-wave Born-approximation theory. Our $l$-value determinations support all previous assignments with the exception of the tentative ${9/2}^{-}$ assignment of the 1606-keV state which favors an $l=2\mathrm{}$ fit to the data. We can assign the 1867-keV state as $l=3, \mathrm{and} 16$ other states can be given probable $l$ values or limited to two or three possible $l\text{'}\mathrm{s}$. We can make several tentative placements of levels within the proposed band structure of ${}_{}{}^{173}{}_{}{}^{}\mathrm{Yb}$ through the use of the standard band formula, our preferred $l$-value fits, and our excitation energy determinations.

NUCLEAR REACTIONS ${}_{}{}^{172}{}_{}{}^{}\mathrm{Yb}(d,p)$, ${}_{}{}^{174}{}_{}{}^{}\mathrm{Yb}(d,t)$, ${}_{}{}^{173}{}_{}{}^{}\mathrm{Yb}(d,d^{\prime })$, $E\left(d\right)=14\mathrm{}$ MeV; measured excitation energies, $\sigma (p,\theta )$, $\sigma (t,\theta )$, $\theta =16\mathrm{}-120°$; ${}_{}{}^{173}{}_{}{}^{}\mathrm{Yb}$ deduced $l$, $J$, $\pi$, $S$; enriched targets, DWBA analysis, magnetic spectrograph.

• Received 6 July 1977

DOI:https://doi.org/10.1103/PhysRevC.16.2167