Diode laser spectroscopy of CO2 in the region for the in situ sensing of the middle atmosphere

In situ sensing of atmospheric CO2 with laser diodes near 2.05 μm: a spectroscopic study

“…The calculated value from the CDSD databank [7] is close to the experimental results. This trend is quite the same that the trend obtained in the 1.60 lm region [3]. In this region we demonstrate that the experimental data obtained by Fourier-transform spectroscopy and by diode laser spectroscopy were close on thirteen lines of the (3 0 0 1) III ‹ (0 0 0) band of CO 2 .…”

“…With these instruments, carbon dioxide is measured in the upper troposphere and the lower stratosphere by means of a commercial Anritsu InGaAs laser diode emitting in the 1.60 lm region [3]. The device is connected by means of an optical fiber to an optical multipass cell which is operated open to the atmosphere and provides a 56-m absorption path length (28-m for the micro-SDLA sensor).…”

“…The CO 2 concentration is retrieved from the atmospheric spectra using the Beer-Lambert law and an appropriate molecular model. The technique was shown to be efficient to monitor stratospheric CO 2 [3]. Nevertheless, the main disadvantage lies in the weakness of the molecular transitions available in the 1.60 lm region.…”

Intensities and self-broadening coefficients of the CO2 Ro-vibrational transitions measured by a near-IR diode laser spectrometer

“…Recently, Fukabori et al [8,9] reported the line profile study by FTIR with a relatively high resolution compared with those. Pouchet et al [10] observed the m 1 + 4m 2 + m 3 band by a diode laser spectrometer. Henningsen and Simonsen [11] measured another Fermi-tetrad band, (3, 0 0 , 1) II centered at 6348 cm À1 , traditionally called 2m 1 + 2m 2 + m 3 band, by NIR-TDL spectrometer.…”

Validation of spectroscopic gas analyzer accuracy using gravimetric standard gas mixtures: impact of background gas composition on CO<sub>2</sub> quantitation by cavity ring-down spectroscopy

“…The background gas composition of ME5537 (70.98 % N 2 , 18.85 % O 2 , and 10.13 % Ar) implied that the Ar content should be taken into account for the correction. Since CO 2 self-broadening is negligible due to the low concentration of CO 2 compared to that of other components (N 2 , O 2 , and Ar) in the investigated gas mixtures, the total pressure broadening coefficient (TPBC) could be expressed as a function of alien gas PBCs and the partial pressures of the corresponding components: Table 5 shows the reported PBCs for N 2 , O 2 , and Ar, and Table 6 shows TPBCs of all cylinders, with (a), (b), and (c) denoting results obtained independently by Pouchet et al (2004), Nakamichi et al (2006), and HITRAN2004 (Rothman et al, 2005), respectively. Since the coefficients of Ar have not been reported by Pouchet et al (2004) and HITRAN2004, the corresponding TPBCs include only N 2 -and O 2 -related pressure broadening .…”