Spectral observations along the main cut compared to our best-fit radiative transfer model. The blue spectra show the observational data and the red spectra show the models. Each column corresponds to different offsets from the center of L 1498 according to Fig. 1. Each row shows a spectral line, except that the N₂H⁺ (1−0) line is split into three rows corresponding to its different F₁ -transition groups. The green dashed lines indicate the 3σ noise level. Observational parameters are summarized in Table 1.