Octupolar excitation has been investigated with respect to mass-selective ion centering in buffer-gas filled Penning traps for the isolation of an ion species of interest. To this end, off-line test measurements have been performed with the preparation Penning trap of the mass spectrometer ISOLTRAP located at ISOLDE/CERN including a comparison with the conventional quadrupolar excitation. The experimental results are compared to numerical simulations of ions under influence of quadrupolar and octupolar excitation. (c) 2012 Elsevier B.V. All rights reserved.
