Detection Techniques for On-Line Mass Determination with Penning Traps

A Penning trap mass spectrometer is a well established instrument for the precise mass determination of both, stable and short-lived nuclides. For this purpose two different concepts are employed. Masses of stable species are mostly determined by the non-destructive detection of image currents induced in the trap electrodes and a subsequent Fourier transformation (FT). For short-lived nuclides the destructive time-of-flight ion-cyclotronresonance technique (TOF-ICR) appeared to be the method of choice, since the ions have to be released from the trap prior to their detection. Approaching rarely produced nuclides with prolonged half-lives T1/2 or pushing forward to ions with multiple charge states q, the nondestructive Fourier-transform ion-cyclotron-resonance (FT-ICR) technique [1] is very promising. In the first case, the limited ion statistics can be overcome by an extended observation time and secondly, with q > 1, single ion detection sensitivity is easily feasible. Both, the destructive detection with microchannel plate (MCP) detectors or Channeltrons and the detection with the FT-ICR technique will be implemented for advanced mass spectrometric studies with the Penning trap system MATS within NUSTAR at the future GSI facility FAIR.