mass spectrometer true Murray, K., Boyd, R., Eberlin, M., et al. (2013). Definitions of terms relating to mass spectrometry (IUPAC Recommendations 2013). Pure and Applied Chemistry, 85(7), pp. 1515-1609. A mass spectrometer is a measurement device that measures the m/z values and abundances of gas-phase ions. [IUPAC] mass spectrometer measurement device