Physical and abundance profiles along the main cut. The profiles of number density ($n_{{\text{H}}_2}$), kinetic temperature (T_kin), the abundance ratio of N₂D⁺/N₂H⁺, abundances (X_species) are the best-fit results from the non-LTE radiative transfer calculations. The Plummer-like profiles fitted with our density profiles are plotted as green curves and the corresponding Plummer parameters are annotated in green. The purple solid curves show the $n_{{\text{H}}_2}$, T_kin(NH₃), X(N₂H⁺) profiles derived by Tafalla et al. (2004).