Broadband, high-resolution investigation of advanced absorption lineshapes at high temperature

Published

August 23, 2017

Author(s)

Ian R. Coddington, William C. Swann, Nathan R. Newbury, Paul J. Schroeder, Matthew J. Cich, Jinyu Yang, Brian J. Drouin, Gregory B. Rieker

Abstract

Spectroscopic studies of planetary atmospheres and high-temperature processes (e.g. combustion) require absorption lineshape models that are accurate over extended temperature ranges. To date, advanced lineshapes, like the speed-dependent Voigt and Rautian profiles, have not been tested above room temperature with broadband spectrometers. We investigate pure water vapor spectra from 296-1305K acquired with a dual frequency comb spectrometer spanning from 6800- 7200cm-1 at a point spacing of 0.0033cm-1 and absolute frequency accuracy of <3.3e-6cm-1. Using a multi-spectral fitting analysis, we show that only the speed-dependent Voigt accurately models this temperature range with a single power law temperature-scaling exponent for the broadening coefficients. Only the data from the analysis using this profile falls within theoretical predictions, suggesting that this mechanism captures the dominant narrowing physics for these high-temperature conditions.

Citation

Physical Review A (Atomic, Molecular and Optical Physics)

Pub Type

Journals

Keywords

frequency comb, spectroscopy

Citation

Coddington, I. , Swann, W. , Newbury, N. , Schroeder, P. , Cich, M. , Yang, J. , Drouin, B. and Rieker, G. (2017), Broadband, high-resolution investigation of advanced absorption lineshapes at high temperature, Physical Review A (Atomic, Molecular and Optical Physics) (Accessed October 1, 2025)