Multi aspect analysis of observed cores: distribution, emission line detection rates, and distance distribution. Top panel: distribution of observed cores in the Galactic plane. The selected cores with and without detections of NH₃ emission lines are denoted by blue and yellow circles, respectively. The red triangles denote Planck sources not only being part of our sample but having also been previously detected in ammonia by Fehér et al. (2022). Lower left: detection rate distribution of NH₃ emission lines. The grey histogram represents the whole sample of 672 sources where we searched for NH₃ lines. The red histogram represents the number of sources that we detected in the NH₃ (1,1) line and the blue histogram refers to sources we also detected in the NH₃ (2,2) line. The green triangles denote the detection rate for a given 857 µm flux density. Lower right: distribution of distances. Here the grey histogram also refers to the entire sample, while the red histogram visualizes those sources detected in NH₃ (1,1). The blue histogram refers to sources we also detected in the NH₃ (2,2) line.