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TI8 STABILITY STUDY. L. Drosdal , V. Kain. TI8 stability studies. 2 November 2011 (1.5h) – YASP trajectory data. Peaks up to 450 m m from average trajectory observed Pattern is not symmetric!. Magnet current variations.
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TI8 STABILITY STUDY • L. Drosdal, V. Kain
TI8 stability studies • 2 November 2011 (1.5h) – YASP trajectory data • Peaks up to 450 mmfrom average trajectory observed • Pattern is not symmetric!
Magnet current variations • MAD-X simulations using observed variations in magnet currents at extraction/start of TI8 • as field errors: • MSE correlation • Observed variations cause fluctuations up to ~400 mm
MSE error trajectories • Comparing the MSE error simulations to the observed trajectory variations from YASP: • The observed variations are only partly explained! Distribution of MSE variations is not even around average (1):
Orbit error – x0 • To explain the missing peak we investigate an orbit error at x0 • Position of peaks fit well, but is not symmetric – offset in distribution • Source unknown, needs investigation!
Trajectory checks • Using selected Yasptrajectories it is clear that there is a combined effect:
Summary TI8 instability • The overall result can be explained by two factors: MSE current variations X0error – Source unknown! Further investigation using MIA
TI2 flashback • Good fit of MADX simulation of MSE error to yasp data: