A plasma desorption time-of-flight mass spectrometer with a single-stage ion mirror: improved resolution and calibration procedure

Abstract A first order electrostatic ion mirror has been constructed and mounted on a time-of-flight spectrometer coupled to the Uppsala EN-tandem accelerator at The Svedberg Laboratory. In electronic sputtering of CsBr with MeV 127 I ions a highest mass resolution around 10500 at a full-width at half maximum for the cluster ions (CsBr) 2 Cs + has been obtained. The resolution for organic molecules is somewhat lower than this value but still significantly better than in a linear system. The mirror also provides great simplification of the calibration procedure and an improvement in mass accuracy compared with a linear spectrometer. For stable ions, and with the help of an einzel lens, the transmission approaches 100% in the mirror. The mirror is equipped with two stop detectors which make it possible to study the decay of metastable ions.