{"title":"Analysis of periodic temporal changes in the spectral signature of IR sources by modeling of spectral artifacts in FTIR systems","authors":"David Santalices, Juan Meléndez, Susana Briz","doi":"10.1016/j.jqsrt.2024.109320","DOIUrl":null,"url":null,"abstract":"Periodic fluctuations in the incoming spectrum to a Fourier-transform infrared (FTIR) spectrometer often result in spectral artifacts that can compromise quantitative measurements. This study presents a novel method that relaxes the conventional assumption of uniform fluctuations across all frequencies, by modeling the radiance fluctuations with a Fourier series expansion with wavenumber-dependent coefficients. By limiting the incoming spectral bandwidth with an interference filter, it is possible to retrieve the artifact-free average spectrum and to obtain the temporal evolution of the incident radiance. Experimental validation was conducted with transmittance measurements on a methane gas sample whose column density was periodically modulated. This method expands FTIR capabilities, particularly for applications involving fluctuating gases, and enhances the potential for time-resolved analysis in complex environments.","PeriodicalId":16935,"journal":{"name":"Journal of Quantitative Spectroscopy & Radiative Transfer","volume":"1 1","pages":""},"PeriodicalIF":2.3000,"publicationDate":"2024-12-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Journal of Quantitative Spectroscopy & Radiative Transfer","FirstCategoryId":"101","ListUrlMain":"https://doi.org/10.1016/j.jqsrt.2024.109320","RegionNum":3,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q2","JCRName":"OPTICS","Score":null,"Total":0}
引用次数: 0
Abstract
Periodic fluctuations in the incoming spectrum to a Fourier-transform infrared (FTIR) spectrometer often result in spectral artifacts that can compromise quantitative measurements. This study presents a novel method that relaxes the conventional assumption of uniform fluctuations across all frequencies, by modeling the radiance fluctuations with a Fourier series expansion with wavenumber-dependent coefficients. By limiting the incoming spectral bandwidth with an interference filter, it is possible to retrieve the artifact-free average spectrum and to obtain the temporal evolution of the incident radiance. Experimental validation was conducted with transmittance measurements on a methane gas sample whose column density was periodically modulated. This method expands FTIR capabilities, particularly for applications involving fluctuating gases, and enhances the potential for time-resolved analysis in complex environments.
期刊介绍:
Papers with the following subject areas are suitable for publication in the Journal of Quantitative Spectroscopy and Radiative Transfer:
- Theoretical and experimental aspects of the spectra of atoms, molecules, ions, and plasmas.
- Spectral lineshape studies including models and computational algorithms.
- Atmospheric spectroscopy.
- Theoretical and experimental aspects of light scattering.
- Application of light scattering in particle characterization and remote sensing.
- Application of light scattering in biological sciences and medicine.
- Radiative transfer in absorbing, emitting, and scattering media.
- Radiative transfer in stochastic media.