The details of a tuning algorithm are described for minimizing the chromatic error in a final focus system, using the two families of sextupoles incorporated in a chromatic correction section. The chromatic errors are characterized by the beam waist location of off-energy particles with respect to the interaction point location. It is shown that linear combinations of changes in strength to the two sextupole families can move the waist position of off-energy beams independently in the X and Y planes. Measurements at the SLC (SLAC Linear Collider) have shown that the off-energy waist position can be measured as a function of the sextupole multiknob to minimize chromaticity.
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