A Residual Gas Analyzer (RGA), otherwise known as a quadrupole mass analyzer (QMS), is a small mass spectrometer that operates under vacuum to measure which elements, and how much, are flying around in a vacuum chamber.
it reads out spectra like this:
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The Y-axis represents the partial pressure that a given (molecular mass)/(molecular charge) represents within the total pressure of the chamber.
Future sections:
ionization continued
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