DescriptionThe nuclear shell model is the foundational model of nuclear physics. It predicts single-particle and single-hole states above and below closed neutron and proton shells. Experimental measurements of nuclei near the shell closures yield important information on the evolution of nuclear structure away from stability and serve as empirical inputs for improved shell model calculations. In particular, neutron-transfer reactions can be used to probe the the single-neutron states of nuclei near the shell closures. 135Xe (Z=54, N=81) lies just one neutron below the N=82 closed shell. Using the (d,p) reaction on 134Xe, single-particle excitations of the unpaired 81st neutron in 135Xe were observed. This 134Xe(d,pg)135Xe measurement was performed at the ATLAS accelerator facility at Argonne National Laboratory, where the coupled GODDESS (Gammasphere-ORRUBA: Dual Detectors for Experimental Structure Studies) detectors were used to detect reaction protons and decay gamma rays in coincidence. This coincident measurement resulted in the identification of five previously unobserved single-neutron levels in 135Xe.