Massenspektrometer und Verfahren zum Einstellen seiner Analyseempfindlichkeit

A plasma ion source mass spectrometer comprising a plasma ion source 40 for ionizing a sample with a plasma; a mass filter 60 for subjecting the sample ionized by the plasma ion source 40 to mass spectrometry; and an interface unit 50 having an orifice formed in a cone 52, 54 for introducing the sample ionized by the plasma ion source 40 into the mass filter 60. Further the plasma ion source mass spectrometer comprises a first cooler 49 for cooling a plasma generator 41 of the plasma ion source 40 and a plasma generating power source 44; and a second cooler 56 independent of the first cooler 49, for cooling the interface unit 50 and for raising the temperature by changing the cooling efficiency so as to reduce the influence of deposition on the interface unit 50. With this construction, the temperature of the interface unit can be controlled without changing the analysis sensitivity of the plasma ion source mass spectrometer.