Relationship between temperatures derived from NH₃ and dust temperature. Top: NH₃ (1,1) main beam temperature as a function of dust temperature (Montillaud et al. 2015). Bottom: kinetic temperature as a function of dust temperature. The red dashed line marks the 1–1 correlation line. The grey line of the least square fit slope is far from 1, two sources with dust temperatures below 10 K have significantly higher kinetic temperatures. The legend is the same as in Fig. 5.