the dispersion of values obtained at the same distance from the central star (i.e. 1 value at distance 0 – hence null dispersion, 4 values at distance 6 arcsec, etc.)
the dispersion of values obtained at the same distance from the central star (i.e. 1 value at distance 0 – hence null dispersion, 4 values at distance 6 arcsec, etc.)