Air-broadening In Near-infrared Carbon Dioxide Line Shapes: Quantifying Contributions From O₂, N₂, And Ar

Adkins, Erin M.

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https://hdl.handle.net/2142/111573 Copy

Description

Title

Air-broadening In Near-infrared Carbon Dioxide Line Shapes: Quantifying Contributions From O₂, N₂, And Ar

Author(s)

Adkins, Erin M.

Contributor(s)

• Hodges, Joseph T.
• Long, David A.

Issue Date

2021-06-22

Keyword(s)

Lineshapes, collisional effects

Abstract

Line-by-line spectroscopic databases containing CO$_{2}$, such as HITRAN, include so many transitions and bands that it is intractable to provide reference data for every transition and relevant collisional partner. To address this dilemma, theoretical line parameters enabling widespread coverage need to be validated in terms of accurate spectroscopic measurements having well-established uncertainties. In this work, we present frequency-agile, rapid scanning cavity ring-down spectroscopy (FARS) measurements of CO$_{2}$ (30012) $\leftarrow$ (00001) band transitions up to J$^{\prime\prime}$ = 50. These data correspond to foreign broadening by four gas mixtures: air, N$_{2}$, and two Ar-enriched synthetic air samples, with each sample containing CO$_{2}$ at a mole fraction near atmospheric levels. The measured O$_{2}$, N$_{2}$, and Ar foreign broadening parameters in addition to advanced line shape parameters were simultaneously determined using a multi-spectrum fitting algorithm which used constraints for pressure, temperature, and sample composition. These results were compared to theoretical and experimental broadener-specific line shape parameters from the literature. Additionally, requantized classical molecular dynamic simulation results were explored as constraints to enable differentiation between narrowing mechanisms in finite signal-to-noise ratio spectra.

Publisher

International Symposium on Molecular Spectroscopy

Type of Resource

Text

Language

eng

Permalink

http://hdl.handle.net/2142/111573

DOI

10.15278/isms.2021.TM03

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