Relation between the global Cartesian coordinate system of EUHFORIA (X, Y, Z), and the local Cartesian system in which the two CME models are defined (X_l, Y_l, Z_l). The distance from the center t_d, the colatitude θ_i, and the longitude ϕ_i define the initial position of the center of the torus, O_l. The vector OO_l, where O is the center of the domain, corresponds to the X_l axis of the local Cartesian coordinate system.