Plasma mass spectrometry method and apparatus

摘要

A plasma mass spectrometer comprises a plasma ion source (1), electromagnetic excitation means (2) associated with the plasma ion source, an interface (15) for sampling ions from the plasma into a vacuum chamber (10, 16), ion optics elements (4) for directing a stream of ions from the interface, a mass analyser (5) and an ion detector (6). Electromagnetic signal detecting means (17; 11) are located upstream from the ion detector (6) and downstream from the interface (15), providing feedback information for optimizing the parameters governing the plasma. <IMAGE>