Top panel: map of the Galactic central molecular zone obtained with the PILOT experiment at 240 μm. The color scale shows the total intensity in log scale. The overlaid texture based on the line integral convolution (Cabral & Leedom 2000) shows the orientation of the magnetic field projected on the plane, inferred from the measured dust polarization. Bottom panel: intensity as above, overlaid with total intensity contours at 0.1, 0.2, 0.5, and 1 × 10⁵ MJy sr⁻¹. The circles show the location of the 100-pc twisted ring as defined in Molinari et al. (2011). The filled symbols are discussed in Sect. 5.4. The names of key molecular regions are overlaid.