deletions | additions       diff --git a/Velocity [1].tex b/Velocity [1].tex  index cc301dc..5ee9574 100644  --- a/Velocity [1].tex  +++ b/Velocity [1].tex 
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Until now we have considered mass to be the physical quantity that we are trying to model. However we are also interested in momentum and energy. These also have a velocity component.  Again, the uncorrected 12CO gave a fairly incorrect model of the actual data, while the corrected 12CO and the 13CO both gave much more accurate predictions. Shown below are contour plots of the average velocity (weighted by mass) in each region of the image for different observation parameters.