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M. Apollonio IC - London

beam line optics. M. Apollonio IC - London. layout. beam line status: estimated proton flux from measurements rates from GVA1/GVA2 analysis (reminder) optics availability sw availability hw main issues [solenoid/diffuser] conclusions & future plans reduced rate and actions

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M. Apollonio IC - London

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  1. beam line optics M. Apollonio IC - London MICE CM22 - 20/10/2008 - RAL

  2. layout beam line status: • estimated proton flux from measurements • rates from GVA1/GVA2 analysis (reminder) • optics availability • sw availability • hw main issues [solenoid/diffuser] conclusions & future plans • reduced rate and actions • matching MICE MICE CM22 - 20/10/2008 - RAL

  3. Beam Features Beamline Production Optics Diffuser SW/HW issues Conclusions • reminder on desired features • Pm = [140 MeV/c, 240 MeV/c], Dp/p = +/- 10% • easily tunable • matched emittance: • 1 mm rad < eN < 10 mm rad deliverable to MICE • high purity muon beam • high rate “600 muons” per target actuation • [1 Hz, 1 ms window] • acceptable losses for ISIS MICE CM22 - 20/10/2008 - RAL

  4. 1 2 3 4 Beam Features Beamline Production Optics Diffuser SW/HW issues Conclusions p production/capture MICE: p – m decay beam line beam line constituted by 4 parts p decay m transport match to MICE MICE CM22 - 20/10/2008 - RAL

  5. Beam FeaturesBeamline Production Optics Diffuser SW/HW issues Conclusions target working principle • titanium blade dipping at 1 Hz in the ISIS proton beam • intercept just ~1ms of ISIS accelerated beam • withdrawal must be quick to avoid scraping next filling •  extreme accelerations (80g) • beam loss must comply with ISIS requirements [P. Hodgson, CM22 19/10/08] 1 ms 10 ms 20 ms MICE CM22 - 20/10/2008 - RAL

  6. Beam FeaturesBeamline Production Optics Diffuser SW/HW issues Conclusions some key questions: • how many protons per spill are we generating? and then pions/muons? • rate in april/may with a D1-D2 line for protons • how much beam can we “shave” before “disturbing” ISIS operations • [K.Long, CM22 19/10/08]? • initial simulation of ISIS beam with ORBIT and comparison with signals from BLMs • [A. Dobbs, CM22 19/10/08] • how well we understand the line? • alignment • magnets MICE CM22 - 20/10/2008 - RAL

  7. Beam FeaturesBeamline Production Optics Diffuser SW/HW issues Conclusions MICE beamline: magnet configuration and detector locations (march/april) ID1=400 A  PD1=480 MeV/c D1 Dp~30 MeV/c BM2:>29/3 IC2: >29/3 D2 BM1: >29/3 ID2=170 A  PD2=450 MeV/c GVA1: > 4/4 GVA2: > 29/3 MICE CM22 - 20/10/2008 - RAL

  8. Beam FeaturesBeamline Production Optics Diffuser SW/HW issues Conclusions • proton rate @ target • target @ 50/128 Hz • 2ms acq. gate • GVA1/2 active for 100 s • R8BLM1 signal ~ 50 mV • GVA1=14 p/dip(1ms), GVA2= 4p/dip(ms) • it corresponds to 2.6E9 (+/-1.3E9) PoT (G4Beamline) x500 less MICE CM22 - 20/10/2008 - RAL

  9. HEP Test Beam target: 200 mV beam loss at 50 Hz Corresponds to ‘loss’ of: 2.4 × 109 protons per dip 1.2 × 1011 protons per sec Beam FeaturesBeamline Production Optics Diffuser SW/HW issues Conclusions [K.Long] Scaled beam loss: • MICE target • Beam loss: • Corresponding to ‘loss’ of 1.2 × 1011 protons per sec • … i.e. per dip (at 1 Hz) is 2 V i.e. 2000 mV MICE CM22 - 20/10/2008 - RAL 600 good μ/spill from 1.7 × 1012 protons

  10. Beam FeaturesBeamline Production Optics Diffuser SW/HW issues Conclusions [K.Long] Conclusions: • Goal: • Increase particle rate in MICE Muon Beam • HEP Test Beam target: • Indicates that to achieve desired rate may require upgrade to collimation system • Radiation surveys: • To date: • No evidence for dose in DSA or MICE Hall • No evidence for activation of ISIS • Tools for the understanding of beam loss and particle rate • In place … • … but, improvements still required (e.g. r/o BPM) MICE CM22 - 20/10/2008 - RAL

  11. Beam FeaturesBeamline Production Optics Diffuser SW/HW issues Conclusions [A. Dobbs] ISIS Beam MICE CM22 - 20/10/2008 - RAL

  12. Beam FeaturesBeamline Production Optics Diffuser SW/HW issues Conclusions [A. Dobbs] MICE CM22 - 20/10/2008 - RAL

  13. Beam FeaturesBeamline Production Optics Diffuser SW/HW issues Conclusions [A. Dobbs] MICE CM22 - 20/10/2008 - RAL

  14. Beam FeaturesBeamline Production Optics Diffuser SW/HW issues Conclusions Comparing G4Beamline to DATA (june): see how well we understand the Q-poles count rates: G4beamline predictions vs measurements june 2nd june 3rd MC / meas: discrepancy x2 MICE CM22 - 20/10/2008 - RAL

  15. Beam FeaturesBeamline Production Optics Diffuser SW/HW issues Conclusions Comparing G4Beamline to DATA (june) 306 72 GVA1/GVA2= 4.25 MC CASE1 D=6.3% DATA 2230 560 GVA1/GVA2= 3.98 2021 (x6.60) 833(x11.57) GVA1/GVA2= 2.42 D=-29% CASE2 8159 (x3.65) 2603 (x4.66) GVA1/GVA2= 3.13 2016 (x6.60) 1297 (x18. / x1.56) GVA1/GVA2= 0.64 CASE3 D=11% 8945 (x4.01) 5077 (x9.07/ x1.95) GVA1/GVA2= 0.57 GVA2 GVA1 greatest effect, amplified by a long drift MICE CM22 - 20/10/2008 - RAL

  16. Beam FeaturesBeamline Production Optics Diffuser SW/HW issues Conclusions What do we know of Q1-3 ? magnet measurements: g (meas.) = 0.5168+/-0.0011 (u.s.) 0.5125+/-0.0012 (d.s.) Tm-1 @ 50 A g (specs) = 10 Tm-1 @ 1000A Leff(specs) = 853.4 mm [no measurement available] magnet positioning: geometrical survey  slight misalignment Q1-3 axis to tgt point G4Beamline implementation: follows values as given in NOTE 066 (T. Roberts) MICE CM22 - 20/10/2008 - RAL

  17. Beam FeaturesBeamline Production Optics Diffuser SW/HW issues Conclusions TEST: vary Q1-3 Leff to check possible systematics [data] Question: can we be so wrong in determining Leff ? MICE CM22 - 20/10/2008 - RAL

  18. Beam FeaturesBeamline Production Optics Diffuser SW/HW issues Conclusions geometrical survey study Q4-point-1 Q4-point-6 1.76o Inclined_Frame_3 Inclined_Frame_2 Inclined_Frame_1 lowest point ??? mm 24.5 mm MICE CM22 - 20/10/2008 - RAL

  19. z z x y ~3-4 mrad ~15 mm ~15 mm to Q1 25o ISIS beam y slight mis-alignment should not cause great change in rate coordinates in ISIS frame x ~4 mm MICE CM22 - 20/10/2008 - RAL

  20. Beam FeaturesBeamline Production Optics Diffuser SW/HW issues Conclusions • Optics: • 0) Muon BL: P=208 MeV/c, • eN= 7 mm rad “ ... the mother of • all the beamlines “ • Proton BL: derived from • by rescaling magnet • currents according to local • momenta. P=440 MeV/c. Used • since Apr. 2008 for initial • calibrations/set-up. W and WO • decay solenoid (DS). • 2) Pion BL: from (a), ditto (b). • P=440/300 MeV/c. W and WO • DS • 3) Electron BL: from (a), ditto • (b). P=330 MeV/c. W and WO • DS. Used for PID calibrations. • NB: many BLs for different • flavours (p, p, m and e): • needed for detector • calibrations beamline scaling for electrons (similar tables exist for p and pi, using excel tables) MICE CM22 - 20/10/2008 - RAL

  21. Beam FeaturesBeamline Production Optics Diffuser SW/HW issues Conclusions Magnet Calibration Tables B(T)/g(Tm-1)I(A) MICE CM22 - 20/10/2008 - RAL

  22. Beam FeaturesBeamline Production Optics Diffuser SW/HW issues Conclusions Local Momenta at magnet entrances Material Budget Table+dE/dX Current Re-scaling MICE CM22 - 20/10/2008 - RAL

  23. Beam Features Beamline Production Optics Diffuser SW/HW issues Conclusions The case of a 9/10 coil solenoid TPT calculation for p Dx ~ 11 cm Dx ~ 5 cm Dx ~ 4 cm Dx ~ 9 cm • Used transport with (444 MeV/c pions) [K. Tilley]: • http://www.isis.rl.ac.uk/accelerator/MICE/Task%20Notes%20and%20Specifications/beamline%20-%20optics/referencedecks&matching.htm • CM14-7.1-200 Transport.FILE1.dat • all DECAY SOLENOID red • reduced DS (9/10) cyan MICE CM22 - 20/10/2008 - RAL

  24. Beam FeaturesBeamline ProductionOpticsDiffuserSW/HW issues Conclusions • Summary of available CODES • TPT/TTL • pros: • fast and usable for quick evaluation • a lot of previous work (KT + HN) • nice “graphic” output • cons: • sort of black box with funny decks • old documentation • not so easy output • d) magnet parametrisation? • ICOOL it could be used to reproduce the BL • pros: • fast • realistic: decay, material, single particle tracking • easy output • cons: • start from nearly scratch • apertures? (quadrupole hyperbolae etc) • G4Beamline • pros: • a) highly realistic • beam line basically set up • easy to run • nice output. • cons: • not easy to change intial conditions (e.g. target shape/orientation) • few local users (myself ) … need to fetch Tom (expert) for details • G4MICE • pros: • highly realistic • nice output • all comprehensive code: from tgt to KL all the way through MICE • allows matching • easy to get in touch with local users/experts (malcolm, chris, mark, …) • cons: • readiness? • magnet parametrisation? MICE CM22 - 20/10/2008 - RAL

  25. Beam FeaturesBeamline ProductionOptics Diffuser SW/HW issues Conclusions • system tested with air motors running • main issues found: • linear driving(cylindrical drum): needs precise stop • ACTION encoder used to stop disc before reaching the bottom • comment: 2 micro-switch will still be used for emergency only • driving of the bayonet pin • length between holding point of motor shaft and point of reaction force too long and holding area too small  the motor shaft bounce off the gear due to large shaft deflection • ACTION: The motor/gear box holder has been re-designed to increase stiffness.   • carousel • a) gear box used has NOT enough power to drive carousel whit a strongly unbalanced configuration • b) motor shaft bent as in above case • ACTION: worm wheel and gear with 65:1 ratio will be used to replace old design + new motor holder bracket re-designed to increase stiffness. • response time / residue airin the air tube when the motors stop • 3 m long pipe: overrun distance due to residual air = 0.02 mm • 16 m “ “ : “ “ “ “ “ “ = 0.04/0.08 mm • ACTION: mu-switch prior to end: 0.3 mm  mu-switches should be OK • back-pressure created when valve shuts before air exhausts • ACTION: MD to design logic sequence to overcome problem • magnetic effect on the air motors • ACTION replace the 3 air-motors with non-magnetic ones. Briggs Air motor contacted [15 days ago] and specs given • [P. Lau - Oxford] MICE CM22 - 20/10/2008 - RAL

  26. Beam FeaturesBeamline ProductionOptics Diffuser SW/HW issues Conclusions • - the relay driver board design finished just before mechanical tests • manufacturing postponed to add possible modifications to design • tests indicate control logic to be modified • electronic crate some minor change • other CEG commitments  slow down the process • no definite date on completion available • contact with RAL experts for installation (electronic issues) • [Mike Dawson - Oxford] m.apollonio UKNF meeting - Trinity College, Oxford - 15/16 Sep 2008 26 MICE CM22 - 20/10/2008 - RAL

  27. Beam FeaturesBeamline ProductionOptics Diffuser SW/HW issues Conclusions summary beam line status: • x500 less proton rate changed completely BL priorities: we need to produce/transport enough m • optics: • mainly available from main one with rescaling – need to check material budget for every specific case! • caveat when matching with MICE optics • beam characterisation (actual emittance)[e.g. emittance via TOFs, M.Rayner Analysis meeting] • hw main issues [solenoid] future plans: • ISIS beam simulation to tackle rate problem • comparison with data • change of tgt orientation (sim) ORBIT/G4xxx • PSI 9/10 optics  transmission study • alignment issues • optics matched with MICE MICE CM22 - 20/10/2008 - RAL

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