High resolution Fourier transform spectrometry in the visible and ultraviolet regions

Abstract

The extension to the visible and ultraviolet regions of Fourier transform spectroscopy (FTS), traditionally regarded as a technique for the infrared, has increased the range of its applications to analytical atomic spectroscopy, astrophysics and atmospheric physics. The relative advantages of FTS and grating spectroscopy have to be assessed differently at these shorter wavelengths; it is shown that the very accurate wavenumber scale and the high resolution attainable are usually the most important advantages offered by FTS. The signal-to-noise ratios that can be obtained with the two types of spectrometer with the same source and the same resolution are compared for absorption and emission spectra, and for scanning and multi-channel grating spectrometers. The suitability of FTS for upgrading databases, both for atomic emission spectroscopy and for astrophysical and atmospheric physics applications, is discussed and illustrated with examples of advances made in all these fields.