An instrument in which beams of ions are separated (analysed) according to the quotient mass/charge, and in which the ions are measured electrically. This term should also be used when a scintillation detector is employed.
Orange Book, 2nd ed., p. 201 (http://media.iupac.org/publications/analytical_compendium/)
PAC, 1991, 63, 1541. 'Recommendations for nomenclature and symbolism for mass spectroscopy (including an appendix of terms used in vacuum technology). (Recommendations 1991)' on page 1545 (https://doi.org/10.1351/pac199163101541)