WBS 6: Magnetic Shielding B. Filippone and B. Plaster Caltech December 3, 2004

Zeroth-Order Concept cos θ coil: r ~ 35cm; ℓ ~ 300cm 4K ferromagnetic shield: r ~ 40cm; ℓ ~ 300cm superconducting shield: r ~ 50cm; ℓ ~ 300cm (neither shown here) 4-layer µ-metal shielding configuration Large cylindrical µ-metal shields with end-caps: r ~ 106.7cm, 110.5cm, 114.3cm, 118.1cm ℓ ~ 445.8cm, cm, 461.0cm, 468.6cm [J. Boissevain]

Zeroth-Order Concept cos θ coil: r ~ 61cm; ℓ ~ 393cm 4K ferromagnetic shield: r ~ 60cm; ℓ ~ 400cm superconducting shield: r ~ 63cm; ℓ ~ 400cm (neither shown here) 4-layer µ-metal shielding configuration Large cylindrical µ-metal shields with end-caps: r ~ 106.7cm, 110.5cm, 114.3cm, 118.1cm ℓ ~ 445.8cm, cm, 461.0cm, 468.6cm [J. Boissevain]

Estimated Costs 4K ferromagnetic shield –Open cylinder with no end caps 20 mil thickness –Cryoperm option Amuneal quote for r ~ 40cm, ℓ ~ 300cm: $30,000 Scale up to latest reference design of r ~ 60cm, ℓ ~ 400cm: $60,000 –Metglas option Honeywell quote: $515/kg 20 mils thick will require ~70 kg → $40,000 Al cylinder support frame: $8,000 VERY LABOR INTENSIVE: ~5 miles of 2-inch wide Metglas strips !!! 300K ferromagnetic shields –Cylindrical µ-metal shields with end-caps; take baseline 62 mils Larry Maltin (President of Technical Products at Amuneal): –“…confident that we could engineer, fabricate, anneal, and install such a [sized] shield…” Cost estimate for largest cylinder with end caps: $60,000 → ~$250,000 for 4 If want larger spacing between layers: $300,000 ~3 to 6 month lead time (freight truck shipping) and will require some on-site assembly 4-layer structure estimated to weigh ~2.5 English tons

Estimated Costs Superconducting shield –Not as well thought out at this point –Proposed idea is to melt lead and pour into a cylindrical Al casting frame Will require design engineering efforts –Estimate: $100,000 $100,000 is estimated cost in pre-proposal No experience yet; crude guess is $50,000 In-house vs. out-sourcing “Room-sized” box-type µ-metal shield or large tri-axial square Helmholtz bucking coils –Estimate for thin (14 mil) box-type (or large cylindrical) shield: $75,000

Estimated Costs AC demagnetization circuit for the ferromagnetic shields –Demagnetizing prototype Cryoperm and µ-metal shields has proven to be difficult (later talk) –High-power, variable-frequency, programmable AC power supply: $25,000 –Demagnetization circuit supplies: $5,000 Technical/Engineering/Machining work at Caltech –Support for design engineer and machinist for assistance with integration of shielding with experiment –Estimated labor costs: $30,000 Note: We did not include expenses related to materials/construction of support structures for the shielding (only for design engineering)

Costs Roll Up WBS 6: Magnetic Shielding Layer Ferromagnetic Shield$360, a 0.3K Ferromagnetic Shield$60, b 300K 4-Layer Ferromagnetic Shield$300, Superconducting Shield$50, Other Shielding (e.g., “room-sized”)$75, AC Demagnetization Circuit$30, Technical/Engineering/Machining Support$30, TOTAL$545,000 Risk Level [ 1 = lowest; 3 = highest ] [Pre-Proposal: $415,000]

Proposed Schedule Personnel during construction phase (1.0 FTE): 1 faculty; 1 post-doc; 1 design engineer; 1 machinist; undergraduate student(s) and/or 1 graduate student Rough Timeline (assuming funding available FY2007) Finalize shield design/geometry Finalize/integrate support structure Procure ferromagnetic shields Construct/test superconducting shield Procure AC demagnetization equipment Install all magnetic shielding Install/test AC demagnetization circuit..... potential hold-ups

300K Four-Layer Shield r = 106.7cm, 110.5cm, 114.3cm, 118.1cm (nominal design) r = 106.7cm, 115.0cm, 125.0cm, 135.0cm r = 106.7cm, 120.0cm, 135.0cm, 150.0cm

WBS 7: Magnets B. Filippone and B. Plaster Caltech December 3, 2004

Overview of Magnets Magnets to be constructed –cos θ coil for static field 1-10 mGauss DC field; ±0.1% spatial uniformity; temporal stability –Solenoid as “π/2 r.f.” 3 He and neutron spin-flip coil 0.1 mGauss AC field; Hz; 1.58 second duration –Spin-dressing cos θ coils Field parameters to be defined … Accompanying instrumentation needs –Highly-stable AC and DC power supplies –Mapping hardware and probes for field monitoring Labor costs (design engineering and machining/construction) and raw materials will comprise the core costs for WBS 7 –As opposed to mostly procurement costs for WBS 6

Zeroth-Order Concept static cos θ coil“π/2 r.f.” solenoid spin-dressing cos θ coils [180° phase difference] 4K ferromagnetic shield Χ x y superconducting shield

Estimated Costs Design and construction of static cos θ coil: $130,000 –¼-scale prototype already constructed at Caltech → have acquired experience with design and machining efforts (later talk) Design engineering/integration labor costs: $20,000 Materials and supplies: $30,000 Machining/production labor costs: $80,000 –Assuming out-sourcing; in-house could lead to reduction Design and construction of “π/2 r.f.” solenoid: $20,000 –Solenoid → design and construction should be simpler (in principle) Design engineering/integration labor costs: $5,000 Materials and supplies: $10,000 Machining/production labor costs: $5,000

Estimated Costs Construction/integration of spin-dressing coils: $150,000 –Prototype AC cos θ coils to be built as part of the R&D efforts at Caltech Design engineering/integration labor costs: $20,000 Materials and supplies: $50,000 Machining/production labor costs: $80,000 –Assuming out-sourcing; in-house could lead to reduction AC and DC power supplies: $60,000 –Require highly-stable power supplies and stabilization circuits DC power supply with accompanying stabilization circuit for the static cos θ coil: $30,000 Low-frequency AC power supply for “π/2 r.f.” spin-flip solenoid: $10,000 High-frequency AC power supply for spin-dressing coils: $10,000 Computer-controlled interface for all power supplies: $10,000 –Possibly coupled to AC demagnetization circuit in WBS 6

Estimated Costs Mapping hardware and probes for (possible) in-situ real-time field monitoring: $80,000 –DC field profile independent of 3 He co-magnetometry –Appropriate tuning of AC fields Computer-controlled positioning/stepping hardware and readout (difficulties due to the cryogenic environment): $50,000 Engineering for integration: $10,000 Cryogenic 3-axis fluxgate magnetometers and probes: $20,000

Costs Roll Up WBS 7: Magnets 7.1 Static Field cos θ Coil$130, r.f. Spin-Flip Coil$20, Spin Dressing Coils$150, AC and DC Power Supplies$60, Field Monitors$80,0001 and 3 7 TOTAL$440,000 Risk Level [ 1 = lowest; 3 = highest ] [ Pre-Proposal: $270,000 ]

Proposed Schedule Personnel during construction phase (2.0 FTE): 1 faculty; 1 post-doc; 1 professional staff member; 1 design engineer; 1 machinist; 1 graduate student (?); undergraduate student(s) Rough Timeline (assuming funding available FY2007) Finalize magnet parameters/geometry Construct/test static cos θ coil Construct/test “π/2 r.f.” spin-flip coil Construct/test spin-dressing coils Procure/test AC and DC power supplies Design/construct field monitors Procure magnetometer/probes Install all components..... potential hold-ups