Abstract

We have measured the infrared spectra of several atmospheric molecules in our laboratory at low temperatures appropriate for atmospheric remote sensing using the high-resolution of a state-of-the-art Fourier transform spectrometer (FTS) and a tunable diode laser spectrometer (TDLS). However, in order to limit the summary to four pages, we present here only the details of the measurements of the collision-broadened half-widths of sP(1,0), sP(3,2), sP(4,1), sP(4,2), and sP(4,3) in the v₂^s-fundamental bands of ¹⁴NH₃ and ¹⁵NH₃ at 198, 245, and 295 K employing the Doppler-limited spectral resolution (~ 10⁻⁴ cm⁻¹) of the TDLS. The temperature dependence of the collision-broadened half-widths of these lines broadened by N₂ has been determined. In addition, we have also measured the air-broadened linewidths of all of these lines at 295 K and the half-width of the sP(3,2) line of ¹⁵NH₃ broadened by ¹⁴NH₃ at 198, 245, and 295 K. Our tunable diode laser spectrometer, the low-temperature absorption cell, and the experimental technique for measuring collision-broadened (Lorentz) linewidths have been described previously.1

© 1993 Optical Society of America