The energy level structure of ${\mathrm{Tl}}^{206}$ has been investigated with the ${\mathrm{Tl}}^{205}\mathrm{}(d,p)\mathrm{}{\mathrm{Tl}}^{206}$ reaction induced with a 12-MeV beam from a tandem Van de Graaff. The proton spectrum was studied with a broad-range magnetic spectrograph at scattering angles from 20° to 90°. A ground-state $Q$ value of 4.276±0.005 MeV was measured for this reaction. Forty-four levels were observed. Below 1.5-MeV excitation energy, levels were found at 263, 305, 635, 650, 802, 998, 1117, and 1335 keV excitation. On the basis of the differential-cross-section and angular-distribution measurements, the ground state and 305-keV state appear to belong to the $\frac{s_1}{\frac{{}_2{}^{}{}_{}{}^{}p_1^{}{}_{}{}^{}}{2}}$ configuration with spins of $J=0\mathrm{} \mathrm{and} 1$, respectively. The 263- and 650-keV states probably are the $J=2\mathrm{} \mathrm{and} 3$ members, respectively, of the $\frac{s_1}{\frac{{}_2{}^{}{}_{}{}^{}f_5^{}{}_{}{}^{}}{2}}$ configuration. The 635- and 802-keV states probably are the $J=2\mathrm{} \mathrm{and} 1$ members, respectively, of the $\frac{s_1}{\frac{{}_2{}^{}{}_{}{}^{}p_3^{}{}_{}{}^{}}{2}}$ configuration. Data on the ${\mathrm{Pb}}^{207}\mathrm{}(d,p)\mathrm{}{\mathrm{Pb}}^{208}$ reaction were taken to aid in the interpretation of the data.

• Received 11 January 1965

DOI:https://doi.org/10.1103/PhysRev.138.B851