Spectral line shaping by exoplanetary atmosphere

Exoplanets are discovered during occultation events. Spectral lines characteristic of stellar emissions are modified and shaped by traversing exoplanetary atmosphere. Several models for radiation transport are presented and compared with observational data. The relative contributions of scattering, absorption and collisional broadening by haze particles are discussed. Accurate measurements of the shape of stellar spectral lines provide critical information about the properties and composition of exoplanetary atmosphere.