Line Broadening and Shifting Studies of the J=5←4 Transition of Carbon Monoxide Perturbed by CO, N2, and O2

2002 ◽  
Vol 212 (1) ◽  
pp. 1-5 ◽  
Author(s):  
V.N. Markov ◽  
G.Yu. Golubiatnikov ◽  
V.A. Savin ◽  
D.A. Sergeev ◽  
A. Guarnieri ◽  
...  
Keyword(s):  
Carbon Monoxide ◽  
Line Broadening

scholarly journals Recovery and validation of Odin/SMR long term measurements ofmesospheric carbon monoxide

2020 ◽  
Author(s):  
Francesco Grieco ◽  
Kristell Pérot ◽  
Donal Murtagh ◽  
Patrick Eriksson ◽  
Peter Forkman ◽  
...  
Keyword(s):  
Carbon Monoxide ◽  
Middle Atmosphere ◽  
Phase Lock Loop ◽  
Polar Regions ◽  
Line Broadening ◽  
Mixing Ratios ◽  
Correct Location ◽  
Relative Differences ◽  
Co Observations

Abstract. The Sub-Millimetre Radiometer (SMR) on board the Odin satellite performs limb sounding measurements of the middle atmosphere to detect molecular emission from different species. Carbon monoxide (CO) is an important tracer of atmospheric dynamics at these altitudes, due to its long photochemical lifetime and high vertical concentration gradient. In this study, we have successfully recovered over 18 years of SMR observations, providing the only dataset to date being so extended in time and stretching out to the polar regions, with regards to satellite-measured mesospheric CO. This new dataset is part of the Odin/SMR version 3.0 level 2 data. The much of the level 1 dataset – except the October 2003 to October 2004 period – was affected by a malfunctioning of the Phase-Lock Loop (PLL) in the frontend used for CO observations. Because of this technical issue, the CO line could be shifted away from its normal frequency location causing the retrieval to fail or leading to an incorrect estimation of the CO concentration. An algorithm was developed to locate the CO line and shift it to its correct location. Nevertheless, another artifact causing an underestimation of the concentration, i.e. a line broadening, stemmed from the PLL malfunctioning. This was accounted for by using a broader response function. The application of these corrections resulted in the recovery of a large amount of data that was previously being flagged as problematic and therefore not processed. A validation study has been carried out, showing how SMR CO volume mixing ratios are in general in good accordance with the other instruments considered in the study. Overall, the agreement is very good between 60 and 80 km altitude, with relative differences close to zero. A positive bias at low altitudes (50–60 km) up to +20 % and a negative bias up to −20 % at high altitudes (80–100 km) were found with respect to the compared instruments.

scholarly journals Recovery and validation of Odin/SMR long-term measurements of mesospheric carbon monoxide

2020 ◽  
Vol 13 (9) ◽  
pp. 5013-5031
Author(s):  
Francesco Grieco ◽  
Kristell Pérot ◽  
Donal Murtagh ◽  
Patrick Eriksson ◽  
Peter Forkman ◽  
...  
Keyword(s):  
Carbon Monoxide ◽  
Middle Atmosphere ◽  
Phase Lock Loop ◽  
Polar Regions ◽  
Line Broadening ◽  
Mixing Ratios ◽  
Correct Location ◽  
Relative Differences ◽  
Co Observations

Abstract. The Sub-Millimetre Radiometer (SMR) on board the Odin satellite performs limb sounding measurements of the middle atmosphere to detect molecular emission from different species. Carbon monoxide (CO) is an important tracer of atmospheric dynamics at these altitudes, due to its long photochemical lifetime and high vertical concentration gradient. In this study, we have successfully recovered over 18 years of SMR observations, providing the only dataset to date being so extended in time and stretching out to the polar regions, with regards to satellite-measured mesospheric CO. This new dataset is part of the Odin/SMR version 3.0 level 2 data. Much of the level 1 dataset – except the October 2003 to October 2004 period – was affected by a malfunctioning of the phase-lock loop (PLL) in the front end used for CO observations. Because of this technical issue, the CO line could be shifted away from its normal frequency location, causing the retrieval to fail or leading to an incorrect estimation of the CO concentration. An algorithm was developed to locate the CO line and shift it to its correct location. Nevertheless, another artefact causing an underestimation of the concentration, i.e. a line broadening, stemmed from the PLL malfunctioning. This was accounted for by using a broader response function. The application of these corrections resulted in the recovery of a large amount of data that was previously being flagged as problematic and therefore not processed. A validation study has been carried out, showing how SMR CO volume mixing ratios are in general in good accordance with the other instruments considered in the study. Overall, the agreement is very good between 60 and 80 km altitude, with relative differences close to zero. A positive bias at low altitudes (50–60 km) up to +20 % and a negative bias up to −20 % at high altitudes (80–100 km) were found with respect to the comparison instruments.

Experimental Spectroscopic Studies of Carbon Monoxide (CO) Fluorescence at High Temperatures and Pressures

2017 ◽  
Vol 71 (10) ◽  
pp. 2353-2366 ◽  
Author(s):  
Olivier Carrivain ◽  
Mikael Orain ◽  
Nelly Dorval ◽  
Celine Morin ◽  
Guillaume Legros
Keyword(s):  
Carbon Monoxide ◽  
Spectroscopic Studies ◽  
Line Broadening ◽  
Two Photon ◽  
Pressure Line ◽  
Photon Excitation ◽  
Pressure Test ◽  
Co Concentration ◽  
Excitation Laser ◽  
Temperature And Pressure

Two-photon excitation laser-induced fluorescence of carbon monoxide (CO-LIF) is investigated experimentally in order to determine the applicability of this technique for imaging CO concentration in aeronautical combustors. Experiments are carried out in a high temperature, high-pressure test cell, and in a laminar premixed CH4/air flame. Influence of temperature and pressure on CO-LIF spectra intensity and shape is reported. The experimental results show that as pressure increases, the CO-LIF excitation spectrum becomes asymmetric. Additionally, the spectrum strongly shifts to the red with a quadratic dependence of the collisional shift upon pressure, which is different from the classical behavior where the collisional shift is proportional to pressure. Moreover, pressure line broadening cannot be reproduced by a Lorenztian profile in the temperature range investigated here (300–1750 K) and, therefore, an alternative line shape is suggested.

Carbon monoxide poisoning

2000 ◽  
Vol 12 (4) ◽  
pp. 354-357
Author(s):  
David R Smart ◽  
Paul D Mark
Keyword(s):  
Carbon Monoxide ◽  
Carbon Monoxide Poisoning
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