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Determination of collisional linewidths and shifts by a convolution method
Applied Optics
|March 18, 2010
Summary
This study introduces a new spectral fitting technique to accurately determine collisional linewidths and shifts from experimental data. The method simplifies spectral analysis by using a Lorentz shape function, proving robust even with sample cell reflections.
Area of Science:
- Spectroscopy
- Physical Chemistry
- Chemical Physics
Background:
- Accurate determination of collisional linewidths and shifts is crucial for understanding molecular interactions.
- Existing methods for spectral data fitting can be complex and require detailed knowledge of instrumental parameters.
Purpose of the Study:
- To develop and present a novel, simplified technique for fitting collisional linewidths and shifts from experimental spectral data.
- To demonstrate the applicability and advantages of the new method using experimental examples.
Main Methods:
- The core method involves convoluting a low-pressure reference spectrum with a Lorentz shape function.
- The convoluted spectrum is then compared with higher pressure experimental spectra to extract collisional parameters.
Main Results:
- The technique successfully fits collisional linewidths and shifts from spectral data.
- The method does not require prior knowledge of the instrument response function or spectral modulation.
- The fitting process demonstrated robustness against the presence of reflections within the sample cell.
Conclusions:
- The described technique offers a straightforward and effective approach to analyzing spectral data for collisional effects.
- This method simplifies spectral fitting, making it more accessible and reliable for researchers in spectroscopy and physical chemistry.
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