Why is fundamental spectroscopy important?
In order to properly characterize gas flow environments and interpret data through laser diagnostics, spectroscopic parameters need to be known to a high accuracy. These parameters are typically well known and tabulated at atmospheric conditions but lose accuracy at the elevated temperature and pressure conditions relevant to many advanced energy and propulsion systems.
The Hanson Research Group is experienced in producing well-defined elevated temperature and pressure conditions through our shock tubes and optical cells. This allows us to directly measure and extend spectroscopic parameters to be accurate at these conditions.
The improved fundamental spectroscopy supports the laser diagnostics critical to the characterization of extreme environments like high-energy flows, combustion environments, and exoplanet atmospheres.
How do we improve fundamental spectroscopy?
In laser spectroscopy, the spectroscopic parameters of interest include line positions, line strengths, and line shapes. To determine these parameters, a laser can be scanned in wavelength at high resolution over one or multiple spectroscopic features at different known conditions. From these data, the parameters can be extracted through the Beer-Lambert relation and a choice of line shape function, such as the Voigt profile. The spectroscopic model can then be validated by direct comparison between the predicted absorbance and the measured absorbance.