Rotational line strengths and self-pressure-broadening coefficients for the 127-μm, a^1Δ_g–X^3Σ_g^-, v = 0–0 band of O_2

Abstract

We measured at 296 K the rotational line strengths and pressure-broadening coefficients for the 1.27-mum, a (1)D(g)-X (3)?(g)(-), v = 0-0 band of O(2) with a Fourier transform infrared spectrometer using an optical path length of 84 m, a spectral resolution of 0.01 cm(-1), and sample pressures between 13 and 104 kPa. The integrated band strength is 7.79(17) x 10(-6) m(-2) Pa(-1) [7.89(17) x 10(-5) cm(-2) atm(-1)], and the Einstein Acoefficient for spontaneous emission is 2.237(51) x 10(-4) s(-1), which corresponds to an upper-state1/e lifetime of 1.24(3) h. The pressure-broadening coefficients decrease with increasing N and range from 19 to 38 MHz/kPa (FWHM). The mean value for the transitions studied is 30.3(21) MHz/kPa [0.1024(71) cm(-1)/atm] (FWHM). The Einstein A coefficient determined here is in good agreement with the widely accepted value of 2.58 x 10(-4) s(-1) initially obtained by Badgeret al. [J. Chem. Phys. 43, 4345 (1965)] more than 30 years ago. The standard uncertainties given above are one standard deviation.

Absolute intensities for the O2 1.27 μm continuum absorption

“…For pure 0 2 samples the gas density po 2 is given by Table 1. The linear-indensity term S02902 is constrained in the analysis using the 296 K value of S 02 determined previously [Lafferty et al, 1998]. In To provide data for atmospheric modeling, we have determined the binary collision absorption coefficients as a function of frequency for the three temperatures, 253, 273, and 296 K. …”

Influence of Atmospheric Solar Radiation Absorption on Photodestruction of Ions at D-Region Altitudes of the Ionosphere

“…The reaction rate coefficients recommended by Sander et al (2011) are used in the model, except for reactions 1-3, 10, 11, 15, 26, 31, 34, 49, 50, and 55-67 of Table 3 where rate coefficients are taken from Smith and Robertson (2008), Lin and Leu (1982), Kalogerakis et al (2009), Fischer and Tachiev (2004), Baulch et al (2005, Altinay and Macdonald (2014), Lafferty et al (1998), Smith and Newnham (2000), Nair andYee (2009), Atkinson et al (2003), Duff et al (2003), Li et al (2014), Herron (1999), Homayoon et al (2014), Fell et al (1990, Butler and Zeippen (1984), Alecu and Marshall (2014), Mellouki et al (1981), Wine et al (1981), and Gierczak et al (2004). It should be noted that the low-pressure-limiting rate coefficients are presented in Table 3 for termolecular association reactions 1 -3, 7, 12, 27, 41, 42, and 47-50 marked by asterisks.…”

Airglow on Mars: Some model expectations for the OH Meinel bands and the O IR atmospheric band

“…Radiative relaxation of O 2 (a 1 ∆ g ) extends for about 1.24 h (A 15 = 2.237 × 10 −4 s −1 , Lafferty et al, 1998). In addition, O 2 (a 1 ∆ g ) may be collisionally deactivated by CO 2 .…”