ABSTRACT
Room temperature measurements of self- and air-broadening coefficients are reported for over 370 transitions covering a range of 0 = J" = 45 and 1 = Ka" = 12 for the nu2 ozone band in the 630 to 800 cm-1 spectral region. In addition, the temperature dependence of air-broadened halfwidth and air-induced pressure shift coefficients have been determined for over 350 spectral lines. A total of 29 O3 absorption spectra (0.005-cm-1 resolution) recorded at various temperatures (29 to -63°C) with a Fourier transform spectrometer were used in the analysis. The spectral line parameters were deduced by analyzing all of the 29 spectra simultaneously using a nonlinear least-squares fitting technique. The results are compared with similar measurements obtained in the ozone nu1 band. Copyright 1997Academic Press
ABSTRACT
High-resolution Fourier transform absorption spectra of ozone broadened by dry air have been recorded at a number of temperatures from -63°C to 29°C. Using a multispectrum nonlinear least-squares procedure, we fit 29 of these spectra simultaneously to determine the air-broadening and shift coefficients and their temperature dependences for 450 lines in the 9-&mgr;m region; most of these belong to the nu1 band. Partial air-broadening results were obtained for 104 additional lines, and room-temperature self-broadening coefficients were also determined for most of the 554 lines measured. These results cover a wide range of rotational quantum numbers, particularly in the R branch, with J" = 55 and Ka" = 12. The variation of the retrieved broadening and shift parameters with the rotational quantum numbers has been examined; particularly interesting behavior of the broadening coefficients is noted as the value of Ka" approaches that of J". The broadening and shift coefficients compare well with previous room-temperature measurements in the nu1 and other bands. The temperature-dependence results are also consistent (within the stated uncertainties) with the few previous measurements of the temperature dependence of air- and N2-broadening coefficients in other O3 bands, but disagree with the mean value given in the HITRAN compilation. Copyright 1997Academic Press