Power Supply Ripple
Asequesed and for your information Miriam has described herrecent studies as follows:A principal component of the planned upgrade to a high luminosity LHC (HI-LHC) is the replacement of the high field quadropole magnets - the so called "inner triplet". The long term beam stability can be significantly reduced by magnetic field errors, miasalignment of the magnets and by irregularities in the power supply (ripple). The recent batch of fifteen or so studies, involving over one and a half million cases or Work Units each of one million turns (for a stable beam), are aimed at determining the maximum allowable tolerances for the power supply ripple assuming the known field and alignment errors.

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