N₂H⁺(1−0) spectra around 100 km s^-1 toward mm1a and mm1b. The green lines show N₂H⁺ fits taking into account the whole hyperfine structure whereas the black lines show two-component Gaussian fits to the isolated hyperfine structure line −8.0 km s^-1 from the central peak. Peak velocities (corrected for the −8.0 km s^-1 offset) and line widths of the Gaussian fits are presented in Table 3.