Ammonia observations of Planck cold cores

The ammonia column densities range from 3.6*10^14^ to 6.07*10^15^cm^-2^, with a median value of 2.04*10^15cm^-2^. The fractional abundances of ammonia range from 0.3 to 9.7*10^-7^, with an average of 2.7*10^-7^, which is one order of magnitude larger than that of massive star-forming (MSF) regions and infrared dark clouds (IRDCs). The correlation between thermal and nonthermal velocity dispersion of the NH_3_(1,1) inversion transition indicates the dominance of supersonic nonthermal motions in the dense gas traced by NH3, and the relationship between these two parameters in Planck cold cores is weaker, with lower values observed for both parameters relative to other samples under our examination.

The cumulative distribution shapes of line widths in the Planck cold cores closely resemble those of the dense cores found in regions of Cepheus, in addition to Orion L1630 and L1641, with higher values compared to Ophiuchus.