CS Cha gas emission and kinematics. Upper row: ¹²CO moment 0, the best model using the geometry recovered from the kinematic fit, and the residuals. Scale bar represents 20 au at the distance of the source. Lower row: ¹²CO peak velocity in the line of sight, with the best model calculated with the parameters from Table 2, and the residuals. The dashed line shows the mask used for the fit.