Decoupling of beams previously coupled by effective stand-alone solenoid fringe fields

Lars Groening

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arXiv · 1403.6962

Decoupling of beams previously coupled by effective stand-alone solenoid fringe fields

Lars Groening

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Abstract

Beams passing through a solenoid fringe field experience x-y coupling and change of their eigen-emittances. As reported previously (C.~Xiao et al., Phys. Rev. ST Accel. Beams 044201, {\bf 16} 2013) constant settings of a subsequent decoupling section can be found such that variation of the fringe field strength will not change the Twiss parameters $β$ and $α$ in both transverse planes at the exit of the decoupling section. For time being this feature was understood for a generic beam line but not to the generality to which it is observed. This report is on explanation of the convenient decoupling of fringe-coupled beams by any beam line that provides decoupling. For better coherence this report includes recapitulation of previous works.

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Lars Groening. 2014-10-23. Decoupling of beams previously coupled by effective stand-alone solenoid fringe fields. https://arxiv.org/abs/1403.6962

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