New Method of Dispersion Correction in the Pep-II Low Energy Ring
  The sextupole magnets in the Low Energy Ring (LER) of PEP-II are grouped in pairs with a phase advance of 180 degrees. Displacing the magnets or moving the orbit to displace the beam in the magnets in an antisymmetric way creates a dispersion wave around the ring. This can be used to correct the vertical dispersion in LER without changing the local coupling. Results from simulations are shown. 
I. Reichel, Y. Cai