Nuclear Structure of theN=82Isotones

The nuclear structure of the $N=82\mathrm{}$ isotones ${\mathrm{Ba}}^{138}$, ${\mathrm{La}}^{139}$, ${\mathrm{Ce}}^{140}$, ${\mathrm{Pr}}^{141}$, and ${\mathrm{Nd}}^{142}$ has been studied using the single-proton-transfer reactions (${\mathrm{He}}^3,d$) and ($d,{\mathrm{He}}^3$) on ${\mathrm{La}}^{139}$, ${\mathrm{Ce}}^{140}$, and ${\mathrm{Pr}}^{141}$ targets. Distorted-wave analysis of the angular distributions has been used to determine angular momentum transfers and spectroscopic factors for states up to about 3-MeV excitation. The experimental data are compared with recent shell-model calculations, and in particular with the results of calculations using a new simplifying coupling scheme, the pseudo spin-orbit coupling scheme.