Additional moment maps of the centroid fitting. Panels show the line width, ΔV (left), the peak optical depth, τ₀ (center), and the error of the centroid fitting, δv₀ (right). Note that for τ₀ < 1 one can assume the line profile to be well presented by a Gaussian, while for τ₀ > 5 the line profile has a saturated core, i.e., a very flat top (see Eq. 2). The beam size is depicted in the lower-left corner, and only regions where I₀ > 5σ with σ = 1.1 mJy beam⁻¹ are shown.