The influence of injection parameters on mass fractionation phenomena in radiocarbon analysis

Three different possible sources of mass fractionation have been investigated in an accelerator mass spectrometer system using sequential injection, namely: the influence of the accelerating/decelerating gaps in front of- and after the bouncing magnet, the influence of changes in the ion trajectories for the three carbon isotopes during bouncing and finally the influence of beam intensity. Measurements have indicated that the first two of these sources on the isotopic ratios measurements can be neglected. On the other hand, it was demonstrated that increasing beam intensity influences the 14C/12C ratio and to a lesser extent the 14C/13C ratio. This is probably related to space charge effects