Sketching Basic Kicker System Parameters W. Bartmann, T. Fowler, B. Goddard, T. Kramer

Motivation Increase number of kicker modules such that each module only contributes a kick below system endangerment thresholds. Investigate a segmented system to: Limit beam perturbations by pre-fired kicker(s) Subsequently avoid asynchronous beam abort. Limit the consequences of missing modules during beam extraction. Ease the feasibility of (several) redundant modules (hot spares).

Summary of 1 st assumption (last meeting) Total required FCC MKD kick: 0.15mrad (25T.m) (for layout with Quad-window) Available beam line length: ~100m; b=500m Max. acceptable kick on circ. beam: 2.75σ → 0.75µrad 200 modules are needed for an individual module kick of <0.75µrad. Probably too high – should be reduced to 1σ to stay on the safe side. Reduce to 150m.

Relation between max. acceptable kick, max. kick per module and beta

Possible system configuration Assuming design based on LHC MKD like magnet. For b=150m and max. perturbation of 1s a max. kick of 0.52µrad/module is allowed. Total system would consist of spares = 300 modules. B.dl = T.m per module; module kick: 0.517µrad Module length 30cm -> 87m mag. length; total physical length ~125m Module length 26cm -> 75.4m mag. length; total physical length ~112m

Reference for assumptions: LHC MKD system Distances between magnets: Chamber head: 46 mm (LHC MKD) Usually 120 mm between magnets but: 400 mm for vacuum pump between every 2 nd magnet (~3 m) and 275 for valve every 5 th magnet (~8m) Kept the same as 1 st assumption - to be evaluated with vacuum specialists.

Magnet Parameters B-field: 0.29 T Inductance L for squared aperture of 36mm: Lm= 0.4µH Current: I= 8.3 kA Required Voltage: 5.25 kV (t.b.c) Generator main capacitance: 1.02 µF Parameters (per module) B.dl [T.m] k [µrad]0.517 Length [mm]300 Aperture (h) [mm]36

Still to be done Basic design of pulse generator Switch and main capacitor circuit Freewheel circuit Droop compensation ( 350µs!) Switch trigger circuits Integration aspects 3D Magnet size Vacuum System Switch (stack) size Capacitor sizes Etc …