Nuclear Structure Studies in Tellurium Isotopes with (d, p) and (d, t) Reactions

Shell-model states in the isotopes 123, 124, 125, 126, 127, 129, and 131 of Te have been investigated via ($d, p$) and ($d, t$) reactions with a typical resolution of 40 keV. Distorted-wave Born approximation calculations were used for the identification of the orbital angular momentum of the captured neutron in ($d, p$) reactions. The $\frac{11}{2^{-}}$, $\frac{3}{2^{+}}$ and $\frac{1}{2^{+}}$ neutron subshells in the 50-82 neutron shell are found to be filling in these isotopes, although the $\frac{3}{2^{+}}$ and $\frac{1}{2^{+}}$ subshells are not filling as rapidly as one would normally expect. There is also found some indication of the $\frac{7}{2^{-}}$ and the $\frac{3}{2^{-}}$ subshells from the next major shell filling in the heaviest isotopes. The $\frac{3}{2^{+}}$ single-particle state is found to lie the lowest in the isotopes 131 and 129, while $\frac{11}{2^{-}}$ and $\frac{1}{2^{+}}$ are found to lie the lowest in the isotopes 127 and 125, respectively. Single-particle energies have been calculated using pairing theory.