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Updated: Jun 13, 2026
07:38
Characterization of Biological Absorption Spectra Spanning the Visible to the Short-Wave Infrared
Published on: January 10, 2025
Summary
This study measured water vapor absorption cross sections for the atomic iodine laser. A formula was derived to estimate absorption for various water vapor and air pressures.
Area of Science:
- Spectroscopy
- Atmospheric Chemistry
Background:
- Accurate absorption data is crucial for laser applications and atmospheric modeling.
- Water vapor significantly impacts atmospheric transmission at specific wavelengths.
Purpose of the Study:
- To determine absolute absorption cross sections of water vapor and air mixtures.
- To provide a predictive model for water vapor absorption across varying pressures.
Main Methods:
- Utilized a temperature-controlled multipass absorption cell.
- Employed a high-resolution Fourier transform spectrometer for measurements.
- Analyzed data using multiple quantitative techniques.
Main Results:
- Measured absorption cross sections in the chemically pumped atomic iodine laser frequency range.
- Determined the absorption cross section for 2 kPa of water vapor in air to be 1.1 x 10^-24 cm^2.
- Developed an expression for estimating absorption cross sections at any pressure.
Conclusions:
- The derived expression enables accurate prediction of water vapor absorption.
- This research provides essential spectroscopic data for laser systems and atmospheric studies.
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