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COD and optics distortion due to QF41 misalignment. Shinji Machida ASTeC /STFC/RAL 2 December 2010. Recent alignment found. QF41 was 6.5 mm closer to QD41 (N. Bliss.) May cause d istortion of orbit and twiss parameters. No effect on vertical COD
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COD and optics distortion due to QF41 misalignment Shinji Machida ASTeC/STFC/RAL 2 December 2010
Recent alignment found • QF41 was 6.5 mm closer to QD41 (N. Bliss.) • May cause distortion oforbitand twiss parameters. • No effect on vertical COD • Let us estimate them witha hard edge model.
Closed orbit distortion by QF41 (1)pattern • A kink at the location of QF41 and regular waveinthe rest. • Full COD amplitude of less than 1 mmwhenQh=7.539 at 18.4 MeV/c.
Closed orbit distortion by QF41 (2)tune dependence • COD can be a few mm when tune is closed to an integer. • Still not enough to explain observed COD.
Optics distortion by QF41 (1)pattern • Both H and V beta functions aredistorted. • (top) without error. • (bottom) with error.
Optics distortion by QF41 (2)tune dependence • Modulation is moderate.