From left: map of N(o-H₂D⁺), N(p-D₂H⁺), and the N(o-H₂D⁺)/N(p-D₂H⁺) ratio from the reference run F1_01. Each panel reports the result for different snapshots in time. Contour regions represent the H₂ total columndensity above 10²² cm⁻² (cyan). As a reference, we also report the APEX beam used in the observations (18′′), the spatial scale in parsec, and the age of the core (t_core). The maps have been convolved with the APEX beam of FWHM 18′′ and 9′′ for the ortho-H₂D⁺ and the para-D₂H⁺, respectively. The total H₂ column density distribution is shown after convolution with a typical Herschel beam of 36′′. The ratio was calculated on a pixel-to-pixel basis.