Presentation #404.04 in the session Catching Big Air: Giant Exoplanet Atmospheres.
The interpretation of exoplanet transmission spectra often runs into parameter degeneracies, which obscure the true nature of the atmospheric composition and physical properties of the planet. We develop a new semi-analytical method for inversion of binned exoplanet transit spectra and for retrieval of planet parameters. The proposed mathematical technique ameliorates the degeneracy problem by targeting parameter combinations, which can be uniquely determined. The method has a clear geometrical interpretation and treats each observed spectrum as a single vector in the multidimensional spectral space of observed bin values. This vector is then decomposed into a wavelength-independent component corresponding to the spectral mean across all observed bins, and a transverse, wavelength-dependent, component, which contains the relevant information about the atmospheric chemistry. The method is illustrated and successfully validated with several examples of increasing complexity.