Kr^86 and Atomic-Beam-Emitted Hg^198 Wavelengths

Vacuum wavelengths are given for the Hg198 2537- and 3132-A lines and the Kr86 6013- and 5651 A lines, referred to the Kr86 primary standard line 6057 A. The light sources were an Hg198 atomic-beam and a Kr86 hot-cathode lamp. A vacuum Fabry-Perot interferometer was employed for the measurements. The wavelength of the Hg198 3132 A line was also determined by using the Hg198 2537-A line as the reference standard. The accuracy of measurement of the Hg198 lines is about a factor of 5 higher than that of the Kr86 lines.