Wj. Lafferty et al., ROTATIONAL LINE STRENGTHS AND SELF-PRESSURE-BROADENING COEFFICIENTS FOR THE 1.27-MU-M, A (1)DELTA(G)-X-3-SIGMA(-)(G), V = 0-0 BAND OF O-2, Applied optics, 37(12), 1998, pp. 2264-2270
We measured at 296 K the rotational line strengths and pressure-broade
ning coefficients for the 1.27-mu m, a (1) Delta(g)-X-3 Sigma(g)(-), u
psilon = 0-0 band of O-2 with a Fourier transform infrared spectromete
r 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 ba
nd 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 A coefficient for spontaneous emission is 2
.237(51) x 10(-4) s(-1), which corresponds to an upper-state 1/e lifet
ime of 1.24(3) h. The pressure-broadening coefficients decrease with i
ncreasing 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 obtai
ned by Badger et al. [J. Chem. Phys. 43, 4345 (1965)] more than 30 yea
rs ago. The standard uncertainties given above are one standard deviat
ion.