1. 1 MICE Mtg Oct 2002 Elwyn Baynham RAL Implementation of MICE at RAL Work done in Engineering and ISIS Departments Rutherford Appleton Laboratory Contributors Iouri Ivaniouchenkov Tom Bradshaw Jim Rochford Tony Jones Paul Drumm Elwyn Baynham

2. 2 MICE Mtg Oct 2002 Elwyn Baynham RAL Aims of the Work l Establish the feasibility to install MICE at RAL l Basic questions »Can it fit in the proposed experimental hall »Can the requirements for services infrastructure be met –Use of existing services –Space for installation of new services »Can the safety requirements of RAL/ISIS be met l Impact on cost

3. 3 MICE Mtg Oct 2002 Elwyn Baynham RAL Scope of Presentation l Overview of the Experimental Hall »MICE layout l MICE Infrastructure needs »Global estimates »Specific assessments - schematic/quantitative l Hydrogen system l Cryogenic plant l Chilling water plant l Electrical power services l MICE installation »Alignment, rails, support structure l Safety Issues

4. 4 MICE Mtg Oct 2002 Elwyn Baynham RAL Experimental Hall Inside Bld R5.2 Hall: L = 47 m W = 12 m H = 8 m S = 564 m 2 V = 4512 m 3 Two overhead cranes (8 tonnes each)

5. 5 MICE Mtg Oct 2002 Elwyn Baynham RAL MICE Layout

6. 6 MICE Mtg Oct 2002 Elwyn Baynham RAL MICE Layout

7. 7 MICE Mtg Oct 2002 Elwyn Baynham RAL MICE Layout

8. 8 MICE Mtg Oct 2002 Elwyn Baynham RAL MICE global services needs l Current status of global audit of services l Cryogenic »Helium –Effective cooling power at 4K min 300W - max 600W »Liquid Nitrogen –min 90 L/hr - max 120L/hr l Electrical –min 250kW - max 350kW l Water cooling –min - 100kW

9. 9 MICE Mtg Oct 2002 Elwyn Baynham RAL Hydrogen System: Hydrogen Module Drawing by E. Black

10. 10 MICE Mtg Oct 2002 Elwyn Baynham RAL Hydrogen System schematic layout Igloo Hydrogen buffer tank Hydrogen vent Hydrogen supply bottles

11. 11 MICE Mtg Oct 2002 Elwyn Baynham RAL Cryogenic Plant - cooling requirements l Systems requiring cryogenic cooling »Muon decay channel magnet l 4K supercritical »MICE Instrument –Sc magnets l 4 K 2 phase –H2 absorber l 14-18K gas –He absorber l 4K liquid –Sci Fi detector l 4K

12. 12 MICE Mtg Oct 2002 Elwyn Baynham RAL Cryogenic Plant - cooling requirements l Proposed configuration of refrigeration plant and interface to MICE is described in the paper of Mike Green »Concept of 2 phase for magnet coil cooling »Shields, stops and lead cooling by 14-18K gas »LH2 cooling by 14 - 18K He gas »Estimates of refrigerator power based on this arrangement l Additional requirements »Scintillating Fibre detector - LHe as absorber

13. 13 MICE Mtg Oct 2002 Elwyn Baynham RAL Cooling requirements - Sci Fibre Detector l Scintillating fibre detector option will require substantial refrigeration power l Initial estimates »150W at 4K »1100W at 77K ( liquid nitrogen) l Impact on the installed refrigeration capacity

14. 14 MICE Mtg Oct 2002 Elwyn Baynham RAL Refrigerator Requirements - power audit

15. 15 MICE Mtg Oct 2002 Elwyn Baynham RAL Cryogenic Plant - schematic layout He tank Compressor room Cold box Refrigerator Buffer dewar

16. 16 MICE Mtg Oct 2002 Elwyn Baynham RAL Cooling requirements - Liquid Nitrogen l Refrigerator »to get the full power rating from the refrigerator will require LN2 cooling –consumption - 90 L/hr l Sci Fibre detector will require approx 25 L/hr l Total consumption approx 115 L/hr (3000L/day) l Dedicated cooler may be the best solution

17. 17 MICE Mtg Oct 2002 Elwyn Baynham RAL Cooling Plant implementation l Implementation will need to take into account »staging of MICE –to allow modularity and flexibility »quench requirements » effects of magnetic fields – pneumatic operation »location of compressor plant –provision of building and power for compressors »if He is to be used in the absorbers

18. 18 MICE Mtg Oct 2002 Elwyn Baynham RAL Cryogenic Plant Location Schematic

19. 19 MICE Mtg Oct 2002 Elwyn Baynham RAL Cryogenic Plant Proposed Location

20. 20 MICE Mtg Oct 2002 Elwyn Baynham RAL Chilled water plant and Electrical power l Chilled water »New 1MW water plant will be built for ISIS –we are negotiating with ISIS to upgrade this to 1.5MW »Status –planning permission is granted agreement with ISIS to fund this should be reached by Spring 2003 l Electrical Power –240V system - we have enough power in the hall –3.3kV system new installation will be required

21. 21 MICE Mtg Oct 2002 Elwyn Baynham RAL Experiment support infrastructure l Requirements for mounting of MICE experiment »Beam height assumed 1.8-2m –Increased to avoid cutting of trench in the hall floor »Alignment –requirement – not yet defined –rail system will be required to mount elements of the experiment »Careful planning for the modular build up and testing will be necessary to ensure matching of all components and their services

22. 22 MICE Mtg Oct 2002 Elwyn Baynham RAL Support Structure Guiding railSupporting rail Support system specs: - max load – 5 Tonnes ? - alignment precision along the beam – 5 mm ? transverse the beam – 1 mm ? vertical – 1 mm ? - max movement along the beam – 5 m ? Questions: 4 or more wheels ? Material – austenitic stainless steel (non magnetic) for example 304-S12

23. 23 MICE Mtg Oct 2002 Elwyn Baynham RAL Support Structure: Forces Solenoid coils: J=71.96 A/mm 2 Focusing coils: J=105.88 A/mm 2 Coupling coils: J=95.07 A/mm 2 Correction coils: J=128.89 A/mm 2 Transition coils: J=86.95 A/mm 2 Transition coils: J=44.40 A/mm 2 Correction coils: J=93.33 A/mm 2 1357 32 153 554 137 2162 1554 861550 153 554 137 2162 1554 86 1550 All forces are in kN ! 755 86 608

24. 24 MICE Mtg Oct 2002 Elwyn Baynham RAL Safety at RAL l Objectives »define the hazards specific to the engineering, installation and operation of MICE »confirm the applicable RAL rules for implementation »review implications and feasibility l note these are summarised in the note of Paul Drumm

25. 25 MICE Mtg Oct 2002 Elwyn Baynham RAL Hazards identified for the engineering of MICE »Pressure vessels/vacuum vessels »Hydrogen »X-ray and radiation »Magnetic fields »Cryogenic liquids »RF radiation »Toxic substances (beryllium)

26. 26 MICE Mtg Oct 2002 Elwyn Baynham RAL Safety at RAL »RAL Safety Rules and Protocols will apply to all aspects of MICE Implementation –special requirements for ISIS »The MICE safety case (hazard assessment) should identify the most credible accidents, analysing probability and consequence and the steps needed to reduce the risks to be as low as reasonably achievable. –An independent Safety Review Committee will review the hazard assessment

27. 27 MICE Mtg Oct 2002 Elwyn Baynham RAL Safety at RAL l The principle regulations that will need to be addressed are: » The new explosive gas regulations (ATEX). – A document explaining the explosion protection will be required » Pressure vessel regulations: – Vacuum vessels are classed as pressure vessels and must be designed as such to an agreed International Code. » RAL codes of Practice and Safety Policy » Quality Control Systems

28. 28 MICE Mtg Oct 2002 Elwyn Baynham RAL Hydrogen Safety Issues l The most significant hazard from liquid hydrogen is an explosion » Cold surfaces can cryo-pump oxygen leading to a hazardous situation with the potential for explosion. » Care must be taken to manage faults to ensure that a “chain” of events does not lead to an uncontrolled dangerous situation.

29. 29 MICE Mtg Oct 2002 Elwyn Baynham RAL Hydrogen Safety Issues l Implementation / experience at ISIS » Liquid Hydrogen is currently used in a hydrogen moderator on ISIS although the volume is somewhat different from that expected for MICE. – ISIS uses about 20L, MICE will use around 120L. » The rules and codes of practice for design, installation and operation of a liquid hydrogen system on ISIS are established for this moderator l “These will be the benchmark for MICE”

30. 30 MICE Mtg Oct 2002 Elwyn Baynham RAL Hydrogen Absorber Design l Benchmark design rules » “design must take steps to prevent the condensation of oxygen on any surface that could come into contact with a hydrogen leak”. – This is the defining statement for the engineering of the MICE absorbers. » In essence the design must prevent the ingress of air in normal operation or fault conditions – the oxygen in the system could come from long term cryopumping

31. 31 MICE Mtg Oct 2002 Elwyn Baynham RAL ISIS benchmark design vs MICE H2 Vac Air MICEISIS H2 Vac He Air

32. 32 MICE Mtg Oct 2002 Elwyn Baynham RAL Hydrogen Safety Issues l Implications for MICE design and installation » MICE design of the absorber system must be identical to the ISIS benchmark or at least equivalent » Preliminary designs (schematics) must be produced which will allow a first stage assessment and comparison with ISIS for the MICE Proposal

33. 33 MICE Mtg Oct 2002 Elwyn Baynham RAL Safety Issues - Radiation protection l X-rays from Cavities »800MHz cavities in a magnetic field will produce large dark currents. The level of radiation from this source is difficult to predict with accuracy. A 60cm concrete wall is included in the layout to reduce the radiation level to 0.5 microSV/hr l From ISIS beam »extensive shielding will be required where the beamline passes into B 5.2 - addressed by Paul Drumm

34. 34 MICE Mtg Oct 2002 Elwyn Baynham RAL Safety Issues - Magnetic fields »Limits for the public: – Stray magnetic fields in a normally accessed area must not exceed 0.5 mT(5G - pacemaker issues). »Where work must be carried out in a magnetic fields, the following limits are used: –Partial body exposure (arms, hands and feet: l 2T (20,000 gauss) for short periods (minutes) l 0.2T (200mT/2,000 gauss) for long periods (hours). –Exposure of whole body l 0.2T (200mT/2,000 gauss) for short periods l 0.02T (20mT/200 gauss) for long periods. »Limits for ISIS –injector /control room

35. 35 MICE Mtg Oct 2002 Elwyn Baynham RAL Safety Issues: Magnetic Field At the moment the 5Gauss line is outside the building – some shielding may have to be used.

36. 36 MICE Mtg Oct 2002 Elwyn Baynham RAL ISIS Linac is close to MICE. First indications are that the field is low enough without shielding Field on ISIS Linac

37. 37 MICE Mtg Oct 2002 Elwyn Baynham RAL Safety Issues: Magnetic Field Volume in blue: 1 kGauss field Volume in orange: 5 Gauss field

38. 38 MICE Mtg Oct 2002 Elwyn Baynham RAL Aims of the Work l Establish the feasibility to install MICE at RAL l Basic questions »Can it fit in the proposed experimental hall »Can the requirements for services infrastructure be met –Use of existing services –Space for installation of new services »Can the safety requirements of RAL/ISIS be met l Impact on cost

39. 39 MICE Mtg Oct 2002 Elwyn Baynham RAL Work for Proposal l Continue to develop layout in hall l Audit of services »final iteration for proposal l Safety »absorber design to ISIS benchmark –initial internal review »magnetic field worst case l Impact on cost »continue to develop the cost model with MICE