artificial profiles.[]{data-label="f:gauss"}](test_gauss){width="3.2in"}

We fit single Gaussians to all artificial line profiles. We display a subset of these fits in Figure \[f:gauss\] (those that match the subset of profiles displayed). As expected, the stronger the blue component, the bluer the centroid of the Gaussian. In Figure \[f:vel\_off\], we show the measured  from these Gaussian fits. Over the range we explore (from no blue component to a blue component that is twice as strong as the red component), the measured  changes by more than 5000 [kms$^{-1}$]{}. Even when the blue component is about a third as strong as the red component, the measured  is [$\sim\!\!$ ]{}1000 [kms$^{-1}$]{} different from the true .

![Measured velocity for artificial line profiles. The horizontal black lines represent the velocity of the two components (as measured from their centroid and assuming a rest wavelength of 3945 Å), with the lower and higher velocity components labelled “Photospheric Calcium” and “‘High Velocity’ Calcium,” respectively. The black crosses represent the measured  from a single Gaussian to fit the profiles. The blue X’s represent the measured  from the wavelength of maximum absorption.[]{data-label="f:vel_off"}](vel_off){width="3.2in"}

We also measured the wavelength of maximum absorption. This wavelength is associated with the blue component when it is 