Ion trajectories in quadrupole mass spectrometer with a static transverse magnetic field applied to mass filter

An experimental study has been carried out using a quadrupole mass spectrom eter (QMS) in which a static magnetic field is applied transversely to the body of the filter. These results have been compared with theoretical mass spectra obtained by computing the trajectories of all injected ions using t he local field conditions. Significant improvement in QMS resolution may be obtained under certain magnetic field conditions, and these have been iden tified and explained in tens of the theoretical model.