PdBI channel map of N₂H⁺ (1−0). Contours are −6, −3, 3, 6, 9, 12 times the rms level of the map, 25 mJy beam^-1 (~53 mK). The synthesized beam located at the bottom right corner of the third panel is 10.6 × 5.74 arcsec², with a PA of 11.94°. We note that the rms noise increases at the edge of the images. Last panel shows the PdBI spectrum (red line) at the position of the cross. The IRAM 30 m N₂H⁺ spectrum (black) has been divided by a factor of five to compare the hyperfine structure with the PdBI spectrum.