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We report a new analysis protocol for HCN hyperfine data, based on thePYSPECKIT package, and results of using this new protocol to analyse a samplearea of seven massive molecular clumps from the Census of High- and Medium-massProtostars (CHaMP) survey, in order to derive maps of column density for thisspecies. There is a strong correlation between the HCN integrated intensity,IHCN, and previously reported IHCO+ in the clumps, but IN2H+ is not wellcorrelated with either of these other two "dense gas tracers". The four fittedparameters from PYSPECKIT in this region fall in the range of VLSR = 8-10 km/s,{\sigma} V = 1.2-2.2 km/s, Tex = 4-15 K, and {\tau} = 0.2-2.5. These parametersallow us to derive a column density map of these clouds, without limitingassumptions about the excitation or opacity. A more traditional (linear) methodof converting IHCN to total mass column gives much lower clump masses than ourresults based on the hyperfine analysis. This is primarily due to areas in thesample region of low I, low Tex, and high {\tau} . We conclude that there maybe more dense gas in these massive clumps not engaged in massive star formationthan previously recognized. If this result holds for other clouds in the CHaMPsample, it would have dramatic consequences for the calibration of theKennicutt-Schmidt star formation laws, including a large increase in the gasdepletion time-scale in such regions.

HCN hyperfine ratio analysis of massive molecular clumps