deletions | additions       diff --git a/ch_h2colarge.tex b/ch_h2colarge.tex  index ed998a3..3858631 100644  --- a/ch_h2colarge.tex  +++ b/ch_h2colarge.tex 
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%FIGURE: mcmc column vs density   I successfully made density maps of the W51 cloud, though because the velocity  structure is quite complicated, I need to fit two components to most of the  map. Two-component fits are never particularly stable, so it was necessary to  restrict the parameters being fitted, and even then the results aren't  perfectly reliable. Despite those caveats, there are some reliable fits,  particularly towards the `core' of W51 Main / W51 IRS 2. There are two  high-density components with $n\sim10^5-10^5.5$ at different velocities evident  in Figure \ref{fig:w51h2cofits}. The southern component, centered on W51 Main,  has $v_{LSR}\sim56-59$. The northern component, a strip going through IRS 2  and towards the west, peaks around $v_{LSR}\sim68-69$. A 10 \kms difference  between two extremely dense components, both which are necessarily in the  foreground of the HII region, is shocking (probably, anyway, unless the sound  speed is very high).  \FigureTwo{figures_chH2CO/W51_H2CO_2parfit_v1_densityvelocity.png}  {figures_chH2CO/W51_H2CO_2parfit_v2_densityvelocity.png}  {Density and Velocity fits to the W51 Arecibo and GBT \formaldehyde   data cubes. \todo{Describe why yellow is wrong}}  {fig:w51h2cofits}{1}  \input{solobib}  \end{document}