Example of a radial profile of the rotational temperature T_rot(CH₃OH) as a functionof projected distance ρ from the nucleus in the jet (see text). The empty circles correspond to the entire line profile, and the blue, green, black, red, and pink dots correspond to rotational temperatures measured in bins of Doppler velocity of (−V ; −0.6V), (−0.6V ;−0.2V), (−0.2V ;+0.2V), (+0.2V ;+0.6V), and (+0.6V ;+V), respectively, where V is either the average expansion velocity or half the FWHM of the line. Each velocity bin samples gas either closer to (v_i < 0) or farther away (v_i > 0) from the plane of the sky, i.e., at a cometocentric distance r larger than the projected distance ρ: r = , where . These dots are plotted at the corresponding deprojected radii r of ± 1.667ρ, ± 1.091ρ or ρ.