COLLISIONAL ION ACTIVATION IN THE ION-TRAP BY A 3-STEP TICKLE FUNCTION

The effects of performing ion resonance collisional activation in two steps separated by an intermediate phase were studied. The results sho w that the time duration and the tickle frequency setting used in this intermediate stage determine the phase of the tickle output in the se cond activation stage which ft is essential to control, to ensure the efficiency of the activation process. The following interpretation is offered: the activation process can be efficiently resumed after a per iod of interruption, provided the tickle voltage in the second activat ion step is in-phase with the axial motion of the ions induced by the tickle field during the first activation stage.