Left panel: single Gaussian velocity dispersions derived from the first set of model data cubes of NGC 2403 as a function of the input expansion velocities used to construct the models (see Section 4.3). Right panel: A _n / A _b ratio derived from the second set of model data cubes of NGC 2403 as a function of the expansion velocities (see Section 4.3). Percentage indicates the fraction of profiles having non-zero expansion velocities in the model data cubes.