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Kevin Tilley For Paul Drumm & the beam line group. Beam line commissioning Preparations for Phase1. Definition of Stages. pre-commissioning checks as soon as kit arrives limited avoid later duplication (risk) Magnet Commissioning starts when the magnets are installed & services complete.
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Kevin Tilley For Paul Drumm & the beam line group Beam line commissioningPreparations for Phase1
Definition of Stages • pre-commissioning checks • as soon as kit arrives • limited • avoid later duplication (risk) • Magnet Commissioning • starts when the magnets are installed & services complete. ( all the above for Q1-3, B1, Q4-6 need to be done by 1st Aug (“vault”/ &<shielding). Q7-9 clearly also preferably so. ) • Online Commissioning (pre-Phase 1) • (target commissioning) • beam in beamline • Hand over to MICE commissioning (Phase1) • who has responsibility & directs work. what personnel? • need to define this point
Precommissioning checks • Power supplies • all supplies logically identical • three small supplies for Q1-3 grouped test bed • exercise power supply controls & interlocks (afap) • Q35 magnets • coil checks (electrical insulation) • Dipoles & Quads • install. power supply software control & monitoring of power supplies etc. • cooling: flow switches and temp sensors • Decay Solenoid • plans covered elsewhere (‘Status of PSI Solenoid’ talk) can start magnet field checks proper …
Conv. Magnet Commissioning…. • important measurements: • polarities of magnets • current to field relationship (“linearity plot”) • magnetic alignment: need simple tools to check field centres; • ideal measurements: • field quality/uniformity • effective length note we are not over rich with people to do this!
Quad/Dipole magnetic fields • Cartoon of Hall-probe support: • eg. for Quads: “target” to sit in quad/dipole aperture Array of predetermined positions: eg 5: geometric centre geometric centre +/- x0 geometric centre +/-y0 drop in hall probe magnetic centre:- meas @ geometric ctr meas @ geometric ctr +/-x0/y0 current to field relationship:- meas @ geometric ctr –x0 say. By = - g . x0 -> extract ‘g’ versus I • for Quads: need 1xQIV support, 1xQ35 support • similar for Dipoles: need 1xM1 support.
Decay Solenoid magnetic field? - should we have a go at this? - field polarity not important. • not aware of a method to quantify the field strength • estimation from fringe field?
On-line commissioning – pre-Phase1 • Rough outline of ISIS startup. Intermittent, base rate beam in Synchrotron ideally > ~10/08
On-line commissioning – pre-Phase1 • with beam in ISIS synchrotron (>~10/08?): • MICE target mechanical etc commissioning • particle production measurements from target? (à la Oct06?)
(Ideas for) On-line commissioning – pre-Phase1 • With the target operating: (~ mid Aug –> Step1?) • thread beam through each beam element to the end. • here there is overlap with ABl CM17 proposals for Step 1 • In August, can begin working to establish beam properties:- • beam present / fluxes / alignment thru the beamline to the end. • more complex measurements if TOFs/Ckov/tracker are available. • Follow beam thru each element, but I’d propose emphasis for August = spend time on the upstream end ie: Q1 -> B2 (-> Q6?) (measuring/realigning). These areas become more difficult to get access to as ISIS continues to startup. • then we can go onto Q6 -> Q9 when done & then into Step 1
(Ideas for) On-line commissioning – pre-Phase1 • With the target operating: (~ mid Aug-> Step1?) • take beam through element by element • one at a time and in down-stream order • to establish that (with magnets @ nom field values) • the beam is present at the exit of the beam element • fluxes are approximately as expected • establish alignment is OK :--- • need upstream collimation to do in each case:- • ideally vary each quad & measure following <x> to ascert alignment • realign if necessary • vary dipole to ascertain alignment of dipoles. • realign if necessary • Make basic to the end of Q9 & to MICE position
Beam Diagnostics • Simple diagnostics are required • Polaroid film (all beam – protons(C2H4?)) • Simple “paddle” scintillation detector(all beam – protons(C2H4?)) • More sophistication • Multi-fibre monitoring (all beam – protons(C2H4?)) • Even more sophistication (these will give us the real beam of interest……….) • ToF • Ckov • Tracker (w/out solenoid) • Tracker (with solenoid)
MICE Commissioning (Phase1) • more detailed setup & performance measurements (AB CM17 talk….) I have only one additional point to make against this: re: first idea of making beamsize / position tuning.
Beam tuning: eg. beamsizes • Someone has 6 simultaneous equations to solve on the spot ! (Q4-9) • It would be very useful to develop practical beam software to aid tuning Q4-9 for beamwidths / match. (for step 1 & esp 2). Design codes presently too slow / inadequate. • We’d need: • the underlying beam model software: • quick / represents beamline accurately & can solve. • provision to make special measurements (ie. the input beam?) • software telling us beam data downstream from TOF0 /1 / Tracker ie. sizes (centres) @ p0 . ie. sizes (centres) of “Good muons” @ p0
‘Philosophy’; example for beamwidths: Requires measurement or some estimate of α, β, ε at entry. In our case is the beam @p0 & subset which reaches end.One offMeasure via TOFs: slideable TOF0 for profiles < Q4? • Obtain measurements initial beam at entry (α, β, ε) . • Use together with measurements eg profile monitor beam widths : to fit model to machine. (fit quad fields) • Now have a model of the real machine. • Now specify desired profile / beamsizes eg. at tracker • Solve model for changes to quad fields for this. • ApplyΔk ( new param – model param) to machine • Iterate process if necessary Requires a model of machine which can optimise / solve for changes QUICKLY.What code could represent muon tpt well & solve quickly? (Transport? no? MAD? No?our tracking codes: G4BL/ICOOL/TTL? no? We have a need here in common with design optimisation
EPB + Target end Measurement of input beam:-3 profile monitors in a drift. -> alpha, beta, emittance Model of beamline which can fit to measured beam & solve for required beam @ end Actual measurements of beam through channel and at end.
Idea for Input Beam Measurement Proposed as a ~ one-off measurement Slideable TOF0 at 3 positions:Measurement of α, β, ε at entry for p0 “Good muons” beam via 3 positions of TOF0. Provides measurement of x,x’y,y’ also TOF1