PNNL

Abstract

We present models that allow us to calculate the effects of various linear and low-order non-linear terms on the E x B drift frequency in a cylindrical Penning trap mass spectrometer. These effects translate directly to shifts in the observed ion cyclotron resonance frequency. We show that nonlinearities in the external electrostatic potential interact with the space charge to affect the observations. Similarly, image charge effects are readily incorporated into our model. The model is then used to describe experimental observations and found to largely account for our observations.