Evolution of single-particle structure near the N=20 island of inversion

The single-particle properties of 29Mg have been investigated via a measurement of the 28Mg(d,p)29Mg reaction, in inverse kinematics, using the ISOLDE Solenoidal Spectrometer. The negative-parity intruder states from the f p shell have been identified and used to benchmark modern shell-model calculations. The systematic data on the single-particle centroids along the N = 17 isotones show good agreement with shell-model predictions in describing the observed trends from stability toward 25O. However, there is also evidence that the effect of the finite geometry of the nuclear potential is playing a role on the behavior of the p orbitals near the particle-emission threshold.