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Here we report observations of the two lowest inversion transitions ofammonia with the 70-m Tidbinbilla radio telescope. They were conducted todetermine the kinetic temperatures in the dense clumps of the G333 giantmolecular cloud associated with RCW 106 and to examine the effect that accuratetemperatures have on the calculation of derived quantities such as mass. Thisproject is part of a larger investigation to understand the timescales andevolutionary sequence associated with high-mass star formation, particularlyits earliest stages. Assuming that the initial chemical composition of a giantmolecular cloud is uniform, any abundance variations within will be due toevolutionary state.  We have identified 63 clumps using SIMBA 1.2-mm dust continuum maps and havecalculated gas temperatures for most (78 per cent) of these dense clumps. Afterusing Spitzer GLIMPSE 8.0 $\mu$m emission to separate the sample into IR-brightand IR-faint clumps, we use statistical tests to examine whether ourclassification shows different populations in terms of mass and temperature. Wefind that clump mass and column density show no significant populationdifference, and that kinetic temperature is the best parameter to distinguishbetween the gravitationally bound state of each clump. The kinetic temperaturewas the only parameter found to have a significantly low probability of beingdrawn from the same population. This suggests that clump radii does not have alarge effect on the temperature of a clump, so clumps of similar radii may havedifferent internal heating mechanisms. We also find that while the IR-brightclumps have a higher median virial mass, both samples have a similar range forboth virial mass and FWHM. There are 87 per cent (40 of 46) of the clumps withmasses larger than the virial mass, suggesting that they will form stars or arealready undergoing star formation.

Molecular line mapping of the giant molecular cloud associated with RCW 106 - IV. Ammonia towards dust emission