Abstract

The spectra of uranium and thorium are convenient sources of reference lines for wavelength calibration at the level of a few parts in ${10}^8$. We observed these spectra by laser optogalvanic spectroscopy in commercial hollow-cathode lamps using a single-frequency cw dye laser operating over the wavelength range 422 to 462 nm. Ten uranium and eight thorium lines were measured with an estimated uncertainty of $0.0003{\mathrm{cm}}^{-1}$ by using our Fabry–Perot wavemeter. The results are compared to previous measurements of these lines and are found to be in good agreement with, and 1 order of magnitude more accurate than, values determined by Fourier-transform spectroscopy.

Reference lines in the optogalvanic spectra of uranium and thorium over the wavelength range 694–755 nm

W. DeGraffenreid and Craig J. Sansonetti
J. Opt. Soc. Am. B 19(7) 1711-1715 (2002)

Reference lines for dye-laser wave-number calibration in the optogalvanic spectra of uranium and thorium

Craig J. Sansonetti and K.-H. Weber
J. Opt. Soc. Am. B 1(3) 361-365 (1984)

Accurate wave-number measurements of uranium spectral lines

Byron A. Palmer, Richard A. Keller, Frank V. Kowalski, and John L. Hall
J. Opt. Soc. Am. 71(8) 948-952 (1981)

Reference wavelengths in the spectra of Fe, Ge, and Pt in the region near 1935 Å

Gillian Nave and Craig J. Sansonetti
J. Opt. Soc. Am. B 21(2) 442-453 (2004)

Use of the optogalvanic effect and the uranium atlas for wavelength calibration of pulsed lasers

Norman J. Dovichi, David S. Moore, and Richard A. Keller
Appl. Opt. 21(8) 1468-1473 (1982)