Abstract

To measure small concentrations of molecules, particularly in a metastable state, we have developed a form of double-beam absorption spectrometer. This instrument allows one to use as an absorber a tube in which a dc discharge creates unstable species. The design provides that light emitted from this discharge shall not interfere with the absorption measurement. We use as a background source a second discharge tube emitting the band system whose absorption we wish to observe. We measure the absorption of a single vibrational band of known probability of transition. A detailed analysis of the relative intensities of all the lines constituting the band is then necessary in order to extract the population of the metastable level.

© 1961 Optical Society of America

Slit-Width Error in the Measurement of Absorption Constants

A. Lempicki, H. Samelson, and A. Brown
J. Opt. Soc. Am. 51(1) 35-40 (1961)

Measurements of Infrared Spectral Emissivities of Hot Carbon Dioxide in the 4.3-μ Region*

Richard H. Tourin
J. Opt. Soc. Am. 51(2) 175-183 (1961)

Highly Precise Wavelengths in the Infrared. II. HCN, N₂O, and CO†

D. H. Rank, D. P. Eastman, B. S. Rao, and T. A. Wiggins
J. Opt. Soc. Am. 51(9) 929-936 (1961)

Measurement of Particle and Gas Temperatures in a Slightly Luminous Premixed Flame

Roger C. Millikan
J. Opt. Soc. Am. 51(5) 535-542 (1961)

Some Spectral Emissivities of Water Vapor in the 2.7-μ Region*

Richard H. Tourin
J. Opt. Soc. Am. 51(11) 1225-1228 (1961)