Linewidth along the equatorial axis of the CALYPSO protostellar envelopes. Blue and red dots show the linewidths at positions that have blue- and red-shifted velocities, respectively. Dots and large dots show the C¹⁸O and N₂H⁺ data, respectively. The dashed curve shows the best fit with a power-law model leaving the index γ as a free parameter (Dv ∝ r^γ) in the outer envelope (see Appendix G). The radius of the outer envelope is given by the break radius of the j(r) or j_app (r) profiles (see Tables F.1 and F.2) or the radius where we observe a reversal of the velocity gradients with respect to the inner envelope. The vertical dashed lines show the transition radii between the different datasets (PdBI, combined, and 30m) and the two tracers as given in Table C.1.