An apparatus for separating isotopes, molecules, and molecular fragments according to mass. The sample is vaporized and ionized, and the ions are accelerated in an electric field and deflected by a magnetic field into a curved trajectory that gives a distinctive mass spectrum.
 Example sentencesExamples
-  Time-of-flight mass spectrometers measure the time it takes for each ion to reach the detector because heavier ions travel more slowly than lighter ions.
 -  The emitted isotopes are focussed through a mass spectrometer and measured.
 -  The gas chromatograph separates the substances present, and then each substance is broken into molecular fragments by the mass spectrometer.
 -  It may even carry an instrument like a mass spectrometer to measure material ejected from impact.
 -  An onboard mass spectrometer will then measure the levels of the different isotopes given off at each stage of the baking process.