21.3.23      KEPLER_VDISK

KEPLER_VDISK is a variable that indicates the disk systemic velocity (in km/s). The value is always used to define the velocity field (see KEPLER_VELO result variable).

However, for the radial profile, the usage depends on the /VSYSTEM option. When /VSYSTEM is not present, the radial profile is taken as the maximum brightness of the integrated, velocity aligned, spectrum for at each radius. When /VSYSTEM option is present, the radial profile is taken at the velocity KEPLER_VDISK.