The geometry of the folded light curve is modelled with a combination of up to two Gaussian functions to fit the eclipses and a sine function to account for the presence of an ellipsoidal variability, as described in Mowlavi et al. (2017).
Not all components are necessary present in all models.
Six distinct model types are retained: from the most complete that include two Gaussians and a sine function, to the simplest model with just a sine
(see model_type).