High Resolution FTS in Astronomy at 7 to 15 Microns

Infrared molecular and atomic lines in planets, stars, and dust clouds can only be resolved using the highest available spectral resolution. The Fourier transform spectrometer is presently the only type of spectrometer capable of resolving powers near 105 which can operate at arbitrary wavelengths in the infrared. However, because noise in a spectrum increases with resolution, working at high resolution requires maximum sensitivity. In the thermal infrared, radiation from the sky and warm optics is the dominant source of noise in a spectrum. In order to achieve 105 resolving power on even the brightest sources in the mid-infrared, special techniques must be used to minimize background radiation.