1. Global Magnet Systems including Field Mapping and Infrastructure Vacuum System MICE Project Board 8 th March 2012 M Courthold – RAL R Preece – RAL P Hanlet – IIT/FermiLab

2. MICE Project Board 8 th March 2012 Global Magnet Systems – Definitions and Responsibilities –Top level integration of all MICE magnet sub systems into a complete Cooling Channel - hardware, software, and interlocks –Global consideration of delivery, integration and commissioning schedules and resulting logistical issues –Provide a conduit for dialog between individual sub system owners, infrastructure providers, and control system providers –Keep a watchful eye on overall Cooling Channel integration, to identify deficiencies, oversights, and impending issues 2

3. MICE Project Board 8 th March 2012 Sub System Responsibility Matrix –Initially the main thrust of the Global Magnet Co-ordinators was to produce a Sub System Responsibility Matrix –This specific task was quickly surpassed and has now been replaced by the tasks performed by: –Alan Grant (MICE-UK Project Manager) - with the overall MICE schedule –Andy Nichols (MICE Project Manager) – in convening meetings to gain information regarding the integration of magnets, detectors, and systems (eg infrastructure vacuum system) 3

4. MICE Project Board 8 th March 2012 General Issues and Considerations –The schedule is driven by the delivery of individual sub-systems –Common infrastructure items have been used where possible –For example: –Vacuum, water, and compressed air systems –Power supplies, including circuit-breakers, dump-resistors and diodes –Sensors and controllers - for temperature, pressure, flow, level, etc. –Due to purchasing methods, and existing purchases, it has not been possible or desirable to rigorously enforce this objective, but … –MICE management decided to implement common EPICS Control & Monitoring solutions for all the Cooling Channel magnets, implemented via the DL team, which has ensured a high degree of commonality –Space in the MICE Hall and MICE LCR is very tight, and is now being carefully coordinated by Jason Tarrant (MICE Integration Engineer) –Of special concern have been: –The potential effect of magnetic fields on sub systems and their hardware –The timely production and delivery of mobile and dedicated EPICS control & monitoring systems for testing the Spectrometer Solenoids and AFC module at the vendor and RAL –The infrastructure vacuum system for the Cooling Channel 4

5. MICE Project Board 8 th March 2012 Field Mapping considerations –MICE management decided to limit field mapping at the vendors to acceptance tests only, according to the manufacturing specification –For the Spectrometer Solenoids, this will be performed at Wang NMR at full field using a device produced by Fermilab. –For the AFC module, this will be done at RAL (in building R9), rather than at Tesla Engineering, as agreed in the initial contract, using the field-mapping device produced by CERN. –Full and final field-mapping will be performed in the MICE Hall, using the field-mapping device produced by CERN. 5

7. MICE Project Board 8 th March 2012 Magnet Group and Magnetic Field considerations MICE management set up a Magnet Group, comprising: Mike Courthold, Vicky Bayliss, and Roy Preece at RAL John Cobb and Victoria Blackmore at Oxford University Mike Zisman at LBNL. Heng Pan at LBNL is now included in the work of this group The group is responsible for: Calculating magnetic fields and forces within the Cooling Channel magnets for each of the significant MICE Steps and Cases, with special regard to quenching of one or more magnets. Calculating the effectiveness of the Magnetic Shielding Walls. Calculating the effect of inserting significant ferrous objects into the Cooling Channel volume, to predict: Resultant local distortion of magnetic field and the effect on beam optics Resultant forces on inserted objects, and thereby on Cooling Channel magnets Recalculation of the internal forces and field distribution within the Cooling Channel magnets, as a result of changed geometry and operating currents, due to departures from the TRD specification, by design or accident, during manufacture Producing detailed fringe field maps for the whole MICE Hall, for each of the significant Steps and Cases. Calculating the effect of fringe fields on MICE infrastructure components, and advising re action to be taken to protect magnetically-sensitive components. NB: This becomes quite complicated if there is ferrous content to the objects being considered The group has become very active since its formation, due to the large number of magnetically-sensitive components that have been located through necessity in high fringe- field areas. 7

8. MICE Project Board 8 th March 2012 Magnetic Fringe Field issues All MICE infrastructure components within the magnetic shielding walls (and slightly beyond) will be subject to very high magnetic fields There is no place where the field will be less than 50 Gauss Most of the region will experience fields in excess of 500 Gauss The stray field will affect numerous infrastructure components, particularly: Turbo-pumps (fields > 5 Gauss) (due to eddy-current heating) Rotary or scroll pumps, fans, and motors generally (including air-conditioning units and cranes) Transformers, relays, circuit-breakers (MCBs and RCDs) Electro-magnetic valves, and proximity detectors (which use Hall effect) Cryo-cooler heads and their compressors Computer hard-disks, and other magnetic media Vacuum gauges It has been confirmed that sensitive components can be individually protected with single-layer Mumetal screens, but at a cost (eg - each of the 31cryo-cooler compressors will need a protective screen costing ~£1500 => £47k) These screens can be designed and produced within 7 weeks for any items that are overlooked It is important to keep sensitive components as far from the stray fields as practical, to reduce the risk of malfunction and the consequential cost of remedial protective screening 8

9. MICE Project Board 8 th March 2012 Phase VI, Solenoid mode, 240MeV/c Beta 42 Zone map of field in ZX plane through beam axis (Y=1684mm) (viewed from above) – complete map 9 Bmod = 5.6T max

10. MICE Project Board 8 th March 2012 Phase VI, Solenoid mode, 240MeV/c Beta 42 Zone map of field in ZX plane through beam axis (Y=1684mm) (viewed from above) – 5 to 500 Gauss only 10 NB: Field within Shielding Wall is mostly > 50 Gauss

11. MICE Project Board 8 th March 2012 Magnetic Fringe Field issues - cntd The MICE magnetic shielding walls are effective in shielding the ISIS and MICE Control Rooms from stray magnetic field in all MICE Steps and cases, except for the most energetic cases within Steps 5 and 6. MICE is in the process of seeking approval from ISIS and RAL SHE Group to operate the MICE Cooling Channel magnets in these conditions with restricted access to areas, such as the ISIS & MICE Control Rooms, by means of signs warning of stray magnetic fields It is envisaged that the strength and extent of the stray magnetic fields predicted by the analysis will be checked by taking magnetic field measurements in key areas during running of the MICE operations. Numerous MICE infrastructure components could potentially be seriously affected by the stray magnetic fields, but there are ways to protect them, if they cannot be relocated, by means of Mu-metal screening – but at a significant cost 11

12. MICE Project Board 8 th March 2012 Phase VI, Solenoid mode, 240MeV/c Beta 42 Zone map of field in ZX plane through beam axis (Y=1684mm) (viewed from above) – 5 to 50 Gauss only 12 NB: Field behind Sth Shielding Wall is still 25-50 Gauss Note how far the fringe field extends West & East

13. MICE Project Board 8 th March 2012 Cryocooler Compressor Analysis 13

14. MICE Project Board 8 th March 2012 MICE Vacuum Infrastructure –A MICE vacuum infrastructure is being designed for the Cooling Channel magnets, which will need to: –satisfy the changing needs of the individual magnets during pump-down, cool-down, running, quenching, and warm-up –withstand the high fringe fields in the vicinity of the magnets –keep all pipe-work infrastructure to an acceptable minimum –Staff from RAL and DL will be working together to specify, design, and implement the system in a timely manner to the high standard demanded. –The basic design parameters have already been produced by Mike Courthold and Matt Hills of RAL, and Wing Lau at Oxford University. –Vishal Francis at RAL has accepted the role of on-site co-ordinator for the MICE vacuum infrastructure. 14

15. MICE Project Board 8 th March 2012 Risk Summary –Sub systems suffer damage during transportation to RAL –Need to identify ways to mitigate transport risks –Need to produce acceptance tests before/after delivery –Manpower restrictions/key staff availability –Sub system requirements incorrectly/inadequately defined, requiring corrective action at RAL –Infrastructure, mechanical envelope, installation issues (size, weight, etc.) –There have already been examples of this with both the EMR and Coupling Coils, resulting in modifications to the south mezzanine, the hydrogen delivery systems, and the AFC modules. –Unexpected sub system interactions –Quench consequences and/or forces –Detrimental effect on the control or field profile of neighbouring magnets –Simultaneous arrival of Cooling Channel modules (eg imminent arrival of Spectrometer Solenoid and AFC module), creating logistical and schedule issues. –Late arrival of dependent sub systems –Late arrival of control system software or hardware, infrastructure components, etc. 15

16. MICE Project Board 8 th March 2012 Risk Summary - c ntd –Mobile EPICS control systems might not be available when required –Space in the MICE Hall and MICE LCR is very tight, and could potentially be exceeded in key areas –Logistics, especially the movement of large components, within the MICE Hall will be a challenge with the high density of infrastructue components –The supply of liquid helium in sufficiently large quantities at short notice, following the quench of one or more magnets, is a concern –The present world shortage and cost of liquid and gaseous helium is also a concern –Of special concern is the potential effect of magnetic fields on sub systems and their hardware 16