Abstract

A sealed-off atomic-beam light source which utilizes the single isotope Hg¹⁹⁸ is described. The emitted 2537 A line was investigated interferometrically with Fabry-Perot interferometers. Interferograms are shown for retardations of 0.4, 1.53, and 2.04 m with order numbers 1.6, 6.0, and 8.1 million, respectively. For each retardation, the theoretical contour of the observed fringes is shown. Theoretically predicted fringe contours are shown for retardations up to 6 m, the approximate limit of interference. It is concluded from the interferograms that the Hg¹⁹⁸ 2537 A line has a half-width of 0.0016 cm⁻¹, as compared to 0.012 cm⁻¹ for the Kr⁸⁶ 6056 A line proposed as the new primary standard of length. Owing to the small half-width and the extremely low level of pertubation in the atomic beam, this Hg¹⁹⁸ line would be suitable for the primary standard of length.

© 1960 Optical Society of America

Kr⁸⁶ and Atomic-Beam-Emitted Hg¹⁹⁸ Wavelengths

R. L. Barger and K. G. Kessler
J. Opt. Soc. Am. 51(8) 827-829 (1961)

Wavelength Passed by Hg¹⁹⁸ Zeeman-Split Absorption Filter

Walter G. Schweitzer
J. Opt. Soc. Am. 53(11) 1250-1252 (1963)

Interference at Great Retardations Obtained with a Calcium Atomic Beam Source*

K. W. Meissner and V. Kaufman
J. Opt. Soc. Am. 49(5) 434-438 (1959)

Correction for Systematic Wavelength Shifts in Atomic Beam Devices

R. L. Barger and K. G. Kessler
J. Opt. Soc. Am. 50(4) 352-356 (1960)

Wavelength of Hg¹⁹⁸ Zeeman Filter Relative to that of the 2537-Å Absorption Line of an Atomic Beam

Walter G. Schweitzer and Karl G. Kessler
J. Opt. Soc. Am. 53(12) 1382-1388 (1963)