A commercial electron impact spectrometer operating at an excitation energy of 100 eV and capable of energy resolution of the order of 10 mV is described. The advantages of electron impact spectroscopy for chemical analysis are reviewed with regard to the high resolution achieved. Several aspects of high resolution spectra of H2, N2, CO, and air are examined. Some comparisons are made with other high resolution spectra to indicate the reliability and accuracy of the method and the facility with which the presence of specific elements may be determined.
J. F. Rendina and R. E. Grojean, "A High Resolution Electron Impact Spectrometer for Chemical Analysis of Gases and Vapors," Appl. Opt. 9, 2148-2153 (1970)