Visible absorption cross sections and integrated absorption intensities of molecular oxygen (O₂ and O₄)

Abstract

Abstract. Absorption spectra of gas-phase molecular oxygen and zero air at temperatures of 223 and 283 K have been measured in the laboratory using a coolable multipass-optics gas cell and Fourier transform spectroscopy in the wavelength range 455 to 830 nm (12,000-22,000 cm-•). Net absorption cross sections of the O2 A-, B-, and T-bands at <0.002 nm spectral resolution, and pressures of 100 and 1000 hPa zero air have been determined. Binary absorption cross sections of the collision-induced 04 bands at <0.18 nm spectral resolution and a pressure of 1000 hPa pure oxygen have been determined, with corrections for the O2 T-band absorption. Calculated integrated absorption intensities and, for the O2 A-and B-bands, "effective" Einstein A-coefficients are compared with previous literature values. IntroductionThe near-infrared and visible spectrum of gas-phase molecular oxygen is characterized by (1) discrete structured ro-

Atmospheric extinction properties above Mauna Kea from the Nearby SuperNova Factory spectro-photometric data set

“…The major features are comprised of saturated narrow O 2 lines, including the Fraunhofer "A" and "B" bands, deepest at 7594 Å and 6867 Å respectively, a wide H 2 O band beyond 9000 Å, and H 2 O absorption features in several spectral regions between 6000 Å and 9000 Å. The weak O 4 features at 5322 Å and 4773 Å (Newnham & Ballard 1998) have been neglected in our current treatment. Table 1 shows the wavelength ranges taken to be affected by telluric features for purposes of SN calibration.…”

Near‐infrared absorption cross sections and integrated absorption intensities of molecular oxygen (O2, O2‐O2, and O2‐N2)

“…The FTS is interfaced to a coolable long-path absorption cell (LPAC) containing White's optics [White, 1942], which has been described in detail previously [Ballard et al, 1994;Strong, 1992], in the RAL Molecular Spectroscopy Facility. The LPAC was fitted with gold-coated mirrors and was otherwise configured as in previous oxygen measurements [Newnharn and Ballard, 1998]. Details of the FTS and LPAC configurations are summarized in Table 1.…”

Cavity Ring-Down Spectroscopy of O2–O2 Collisional Induced Absorption

“…In a scanning experiment baseline fluctuations can be interpreted as absorption signal. Note that Newnham et al [5] had to set the baseline to zero at two frequency positions, adding a source of systematic uncertainty, which is avoided in the pressure ramp method.…”

“…Newnham et al [5] employed a long path FT spectrometer, recording the spectrum at 1000 hPa. Extraction of the quadratic pressure dependence was done from this single pressure alone.…”