deletions | additions       diff --git a/CO_velocities.tex b/CO_velocities.tex  index 3d6ff12..8b0a676 100644  --- a/CO_velocities.tex  +++ b/CO_velocities.tex 
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\subsubsection{CO Velocities} \label{CO} CO observations trace gas with mean density around 100 cm$^{-3}$. CO emission associated with the Scutum-Centaurus Arm of the Milky Way is shown in Figure \ref{fig:COarm}, which presents a plane-of-the-sky map integrated over $-50 CB NOTE: This claims in the last paragraph could be tested statistically in a few different ways. The most obvious is to fit a moving-average regression line through the CO map, and confirm that this line (+ uncertainties) overlaps Nessie. The second test is to check whether the curvature in Nessie optimistic is present in the CO data (as the paragraph seems to suggest). One could do this by fitting a straight line through the CO data, and checking whether this is inconsistent with the first regression line. I agree that these will probably be weak tests given the intrinsic width of the CO data, but I would be in favor of {\it some} quantitative argument to back up the first sentence in the previous paragraph. I could run these tests if someone points me to the data used in the figure