• S. Bettoni
  CERN, Geneva
• B. Bolli, S. Ceravolo, S. Guiducci, F. Iungo, M.A. Preger, P. Raimondi, C. Sanelli, F.M. Sardone
  INFN/LNF, Frascati (Roma)

The wigglers of the DAΦNE main rings have been one of the main sources of the non-linearities in the collider. A method to minimize the odd integrated multipoles around the beam trajectory (the even ones tend to vanish due to the periodicity of the device) is described. It consists in displacing the magnetic axis of each pole towards the position of the beam in such a way that the integrated odd multipoles are minimized in each half period of the wiggler. After a study, including multipolar and tracking analysis, has performed to determine the best position of the axes, the wigglers in the DAΦNE main rings have been modified accordingly. To validate this approach magnetic measurements and tests with beam by means of closed orbit bumps have been performed.