PRECISION MEASUREMENTS OF WATER VAPOR SPECTROSCOPY BROADENED BY O₂ FOR ACCURATE DETERMINATION OF POTENTIAL ENERGY SURFACE

Sung, Keeyoon

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https://hdl.handle.net/2142/122518 Copy

Description

Title

PRECISION MEASUREMENTS OF WATER VAPOR SPECTROSCOPY BROADENED BY O₂ FOR ACCURATE DETERMINATION OF POTENTIAL ENERGY SURFACE

Author(s)

Sung, Keeyoon

Contributor(s)

• Gamache, Robert R.
• Toon, Geoffrey C.

Issue Date

2023-06-21

Keyword(s)

Linelists

Abstract

We have investigated collisional broadening and pressure-induced frequency shift for H₂O transitions broadened by O₂. For this, we have obtained one pure and four O₂-mixture spectra of H₂O in the ν₂ region at room temperature using a high-resolution Fourier transform spectrometer (Bruker IFS-125HR) at the Jet Propulsion Laboratory. Using a high-precision spectrum fitting package, Labfit, which adopted non-linear least squares curve fitting algorithm based on a Voigt line shape profile, we have retrieved the two line shape parameters as well as the line positions by fitting all the five spectra simultaneously. It should be noted, however, that their line intensities have been held to the HITRAN values, which improved the precision of the widths and shifts retrieval to a sub% level for most of the transitions. Results from this work have been used to improve the intermolecular potential of the collisional pair, H₂O-O₂, as part of the theoretical model calculations for O₂-broadened H₂O transitions. We will present and discuss the retrieval methodology and the impact of the measurement results on the theoretical model calculations, which are expected to produce more accurate line shape parameters for the entire rovibrational transitions of H₂O in the infrared.ᵃ

Publisher

International Symposium on Molecular Spectroscopy

Type of Resource

Text

Language

eng

Handle URL

https://hdl.handle.net/2142/122518

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