Abstract

To avoid distortions in measurements of spectral-line profiles and photoabsorption cross sections, spectrographs or spectrometers that have instrument widths much narrower than the line widths must be used. For studies of the Doppler-limited, vacuum-ultraviolet (VUV) spectra of atoms and molecules at 300 K or less, this means that resolving powers of about 10⁶ are required. The first Fourier-transform spectrometer (FTS) capable of such resolving power at wavelengths in the 220-180 nm range has been developed and demonstrated by Thorne et al.¹ It was equipped with a beam splitter made from optically contacted fused quartz. We have recently modified this FTS by using a similar beam splitter made from a MgF₂ crystal and have, thus, extended the low-wavelength limit for such high-resolution spectroscopy. The performance of the VUV FTS will be discussed, and applications to the VUV spectroscopy of atmospheric molecules such as O₂ and NO will be presented.

© 1990 Optical Society of America