Abstract

A 5-A dc arc was struck between pure chromium electrodes in nitrogen at 1 atm. The chromium I excitation temperature, averaged over atoms in the center of the arc image, determined by relative emission-line intensities in the near infrared, was found to be (4893 ± 190) °K. The extent of self-absorption was determined from the same lines. Relative <i>f</i> values for 63 lines of chromium I, including the 21 used initially, were determined with precision of 0.33 in log <i>gf.</i> Existing instrumentation and current improvements to the experiment are described.

Forty-Five Relative f Values for High Excitation Iron Lines from the dc Arc Spectrum

Ray Hefferlin
J. Opt. Soc. Am. 49(10) 948-949 (1959)

Relative f-Values for Lines of Cr I

Armin J. Hill and Robert B. King
J. Opt. Soc. Am. 41(5) 315-321 (1951)

Behavior of the dc Iron Arc and Its Usefulness in the Determination of f Values

Ray Hefferlin
J. Opt. Soc. Am. 49(7) 680-685 (1959)

Electron density, temperature, and local thermodynamic equilibrium in low-voltage low-current break arcs: Magnesium

E. O. Degenkolb and J. E. Griffiths
J. Opt. Soc. Am. 67(9) 1235-1240 (1977)

Note on the Temperature Determination of the Iron Arc and the Derivation of the f Values

V. Letfus
J. Opt. Soc. Am. 51(10) 1151-1151 (1961)