A linear combined trap for on-line spectroscopy

The linear combined trap is a superposition of the conventional Paul and Penning traps in one device. Using a four-rod structure, a linear configuration can be constructed. Such a linear combined trap is particularly well suited for catching ions produced externally, since both the effective potential due to the driving RF-field and the DC-magnetic field contribute to the ion confinement. The use of this novel trap for on-line laser and mass-spectroscopy of rare short-lived isotopes is proposed.