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Abstract: This paper is the second of a series that reports results on the measurements of the absorption cross section of SO2 in the UV/visible region at high resolution and that investigates high temperatures in support to planetary applications. Absorption cross sections of SO2 have been obtained in the 29000–44000cm−1 spectral range (227–345nm) with a Fourier transform spectrometer at a resolution of 2cm−1 (0.4500cm MOPD and boxcar apodisation). Pure SO2 samples were used and measurements were performed at room temperature (298K) as well as at 318, 338 and 358K. Temperature effects in this spectral region are investigated and are favorably compared to existing studies in the literature. Comparison of the absorption cross section at room temperature shows good agreement in intensity with most of the literature data, but shows that most of the latter suffer from inaccurate wavelength scale definition. Moreover, literature data are often given only on restricted spectral intervals. Combined with the data described in the first part of this series of papers on SO2, this new data set offers the considerable advantage of covering the large spectral interval extending from 24000 to 44000cm−1 (227–420nm), at the four temperatures investigated. [Copyright &y& Elsevier]

The measurements of the NO2 absorption cross sections by several authors have been considered in order to derive its temperature and pressure dependences in the 13 200–42 000 cm−1 spectral range. The temperature dependence is assumed to be linear in the temperature range investigated (217.0–298.5 K), whereas the influence of the total pressure is expressed as a temperature-dependent broadening coefficient. From measurements performed with mixtures of NO2 in air and in N2, values of γair0 (296 K) and γN20 (296 K) were found to be, respectively, 0.081±0.002 and 0.069±0.003 cm−1 atm−1. The temperature coefficient n obtained in the present work is 0.8±0.1. The parameterization of the cross sections developed in this work can reproduce measured cross sections within 4%. [Copyright &y& Elsevier]

Abstract: This paper describes the status of the 2008 edition of the HITRAN molecular spectroscopic database. The new edition is the first official public release since the 2004 edition, although a number of crucial updates had been made available online since 2004. The HITRAN compilation consists of several components that serve as input for radiative-transfer calculation codes: individual line parameters for the microwave through visible spectra of molecules in the gas phase; absorption cross-sections for molecules having dense spectral features, i.e. spectra in which the individual lines are not resolved; individual line parameters and absorption cross-sections for bands in the ultraviolet; refractive indices of aerosols, tables and files of general properties associated with the database; and database management software. The line-by-line portion of the database contains spectroscopic parameters for 42 molecules including many of their isotopologues. [Copyright &y& Elsevier]

Abstract: The absorption spectrum of dideuterated water, D2O, has been recorded between 8800 and 9520cm−1 by intracavity laser absorption spectroscopy (ICLAS) based on a vertical external cavity system emitting laser (VeCSEL) and by high sensitivity Fourier Transform spectroscopy. The combined analysis of the spectra has allowed attributing 1223 transitions to the D2O species. The spectrum assignment was performed on the basis of the recent results of variational calculations based on an optimized potential energy surface of D2O. A set of 687 energy levels was derived from transitions assigned to eight upper vibrational states, 577 of them being reported for the first time. A detailed line list has been generated. The line intensities were retrieved mainly from the FTS spectrum and the absolute integrated intensities of the 2v 1 + v 2 + v 3 and the v 2 +3v 3 bands dominating the spectrum have been determined. [Copyright &y& Elsevier]