mctf hardware development plans

08/08/07MCTF Hardware Plans 1Fermilab AACMCTF

MCTF Hardware Development Plans

Michael Lamm

Focus on Support for Muon Collider Magnets at Fermilab


MCTF Magnet Effort

• Primary Focus on – Support specific magnet projects for 6D Cooling

Demonstration Experiment• Helical Cooling Channels and Matching Sections

• Coordination with AP and Detector groups

– Very high field solenoid for final stages of cooling• HTS Conductor R&D

• Magnet Design

• Organization of a National Collaboration

• Other tasks– Next generation HCC (newly approved Muons Inc SBIR)

– Collider and IR magnets for Muon Collider

**Called out in MCTF charge**


Helical Cooling Channel

• Cooling Channels proposed by Muons Inc for MANX experiment. (See R. Johnson and K. Yonehara presentations)

• Time scale for experiment: ~2010 • Solenoid, with superimposed helical quad/dipole filled

with low Z material can reduce 6D emittance• No RF Cavity

– HCC field reduced along helix to compensate for dE/dx loss

– Design should be compatible with adding RF in future


Conceptual Design Decision

• Coil geometry tracks central trajectory

• ~0.5 m diameter thin solenoids, offset transversely.

• Dipole and quad fields are a consequence of offset, coil diameter and helical periodicity

• Features – Small magnet volume– Modular assembly of coils– Flexibility in assembling magnet– Able to test concept on a smaller

scale: demonstration magnet

Novel Small Bore Helical Cooling Channel

Magnet Design and tracking studies presented at ASC06 & PAC07 by Vl. Kashikhin and K. Yonehara et al


Design Parameters for Helical Solenoid

Latest parameters from: MOPAS012 PAC07 Vl. Kashikhin et al

Parameter Unit Value

Inner bore diameter m 0.5

Helical Solenoid length m 3.2

Helix twist pitch m 1.6

Radius of beam reference orbit m 0.255

Initial dipole field, BT 1.25

Dipole field gradient,B/z T/m -0.17

Initial quadrupole field, B/r T/m -0.88

Quadrupole field gradient,2B/r/z T/m2 0.07

Initial field, BzT -3.86

Longitudinal field gradient,Bz/z T/m 0.54

NbTi superconductor peak field T 5.7

Operational current kA 10

Operating stored energy MJ 4.4

Coil section length along Z axis mm 20

Superconducting cable length km 3.3

Manageable SC peak field, stored energy, operating current, SC cable length


Outer bandage rings

Inner bobbin

Superconducting coils (one layer, hard bend wound)

Demonstration Magnet

• Features– Use existing SC cable from SSC surplus inventory– Test in Vertical Magnet Test Facility

• This puts some constraints on the geometry of this demonstration magnet while providing large flexibility in test parameters

• Part of STTR phase II proposal from Muons Inc with Fermilab Recently approved!– Labor for design, fabrication and test through STTR– Materials and some contract labor from Fermilab via MCTF/APC

• Goals for Demo magnet– Validate Mechanical

Structure– Develop Field quality

measurement – Study quench protection

issues


Demonstration Magnet (II)

Parameter Model Nominal

Model Max

MANX

Peak superconductor field 3.3 T 4.84 T 5.7 T

Current 9.6 kA 14 kA 9.6 kA

Number of turns/section 10 10 10

Coil inner diameter 420 mm 420 mm 510 mm

Lorentz force/section, Fx 70 kN 149 kN 160 kN

Lorentz force/section, Fy 12 kN 25 kN 60 kN

Lorentz force/section, Fxy 71 kN 151 kN 171 kN

Lorentz force/section, Fz 157 kN 337 kN 299 kNTurns smooth transition area

Coil sections, slightly smaller in diameter to fit into vertical Dewar, are shifted in transverse direction to model MANX system with the orbit radius 0.255 m and helix period 1.6 m.

Model will experience Lorentz forces comparable to MANX experimentFrom: Vl. Kashikhin


Demonstration Magnet Status

• Design work started prior to start of STTR phase II

•Mechanical/Magnetic Design underway

•COMSOL 3D FEM electromagnetic and stress analysis shows coil stress a very manageable <50 MPa at peak field.

• Need approximately 3-4 km of SSC inner cable for MANX experiment. We have acquired over 10 km from SSC cable surplus. Tests will be performed on extracted stands this fall to validate expected strand performance.

• Internal design review sometime in Fall 2007/Winter 2008

• Goal is to test magnet in Fall 2008


HCC Issues

• Demonstration magnet should validate magnetic and mechanical design by end CY08

• Decide if matching sections are required for MANX

• Complete specification for full scale MANX HCC including: field quality and “in situ” field monitoring; interface with particle tracking; cryostat details including helium requirements; powering scheme for dE/dx loss compensation; quench protection; other infrastructure needs

• Need approximately 2 years from final design to magnet fabrication and installation, i.e. need to complete studies in 2008 for a 2010 schedule


High Field Solenoid

• Proposed for end of cooling channel for final emittances• 30-50 T DC, 30-50 mm aperture, 1-2 m length• Goals: Highest practical field, accelerator field quality,

low manufacturing cost, low operating costs• Superconducting for manageable power reqs

– Existing very high field magnets are resistive or resistive/SC hybrids Megawatt Power, one-of-a-kind, expensive to build/operate

– Engineering current density (Je) of HTS materials measured up to 45 T, have a mild dependence on B… however..

– Building this solenoid is beyond present capabilities, although 25-30T HTS solenoids are proposed

• MCTF program for FY07– Conductor testing (Bi2212 wire, Bi2223 and YBCO tapes)– High Field Solenoid Magnet Design– Organizing National Program for High field HTS Magnets


Je(B,4.2 K) of HTS Conductorscirca 2005

Unpublished data, Schwartz, Trociewitz, Weijers & Schneider-Muntau

0

200

400

600

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1200

1400

0 5 10 15 20 25 30 35 40 45 50

B [T]

Je [

A/m

m2]

AMSC 2223 B||ab 2005

AMSC 2223, B || c

YBCO B||ab 2005

YBCO B||c 2005

OST Bi2212 RW

OST Bi2212 B||ab

OST Bi2212 B||c

4.2 K, 5mV/cm

Bi2212YBCO

Bi2223

Private Communication: J. Schwartz

NbTi Limit

Nb3Sn Limit


Conductor Testing at Fermilab

B

SAMPLE

I

B c

b a

IB

Probe for Angular Measurements

Courtesy of E. Barzi


Example of Measurements Performed

4.2 K

1

2

3

4

5

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7

-11.25 0 11.25 22.5 33.75 45 56.25 67.5 78.75 90 101.25

Angle, o

Ic /I

c(7

7K

,0T

)

0T

1T

2T

3T

4T

6T

8T

10T

12T

15T

Bi-2223 BSCCO-2223

0

100

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500

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0 2 4 6 8 10 12 14 16B, T

Ic, A

33K ┴

22K ┴

14K ┴

4.2K ┴

1.8K ┴

33K //

22K //

14K //

4.2 K //

Studies performed on Bi-2223 and YBCO tape (not shown) show Strong angular dependence

Studies performed over a wide range of angles, temperatures and fields

E. Barzi, SC R&D LabAlso extensive temperature and field studies on Bi 2212 wire (not shown)


High Field Solenoid Designs

• Two studies high field solenoid studies related to the MCTF have been performed in the last ~15 months– Steve Kahn and Bob Palmer

• Discussed in MCTF talk at Dec 2006 AAC meeting

• Updated at Low Emittance Workshop

– Vadim Kashikhin and Sasha Zlobin• Presented at Low Emittance Workshop

• Updated version to be presented at MT-20 August 2007

– Parameters• Hybrid magnet with NbTi, Nb3Sn and HTS superconductor

• Utilize Bi-2223 tapes (steel reinforced, long lengths and reasonable Jc)

• Bi-2212 wire is also possible


Analytical model

• An example of the optimum geometry in case when 25% of support material is introduced in the coils. Use parameterization of Bi2223 angular dependence data.

Minimum cost criterion Minimum Diameter criterion

0

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0.00 10.00 20.00 30.00 40.00 50.00 60.00

B, T

DR

, mm

0

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Co

st, u

nit

s

HTS

Nb3Sn

NbTi

Cost

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0 10 20 30 40 50 60B, T

DR

, mm

0

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st, u

nis

HTS

Nb3Sn

NbTi

Cost

Va. Kashikhin


Numerical structural analysis

• An example of the coil support structure (not optimum geometry in terms of cost or size).

B=0T B=50T

HTS Coils NbTi/Nb3Sn Coils

Supports structure Va. Kashikhin

HTS<160MPa, but Bmax~44T


National Collaboration on HTS Magnet R&D

• There is little or no market for HTS materials relevant for high field scientific applications.

• From discussion with HTS Vendors, sustained support from magnet community is needed to make progress. Need effort comparable to successful Nb3Sn Conductor Program

• Proposal “White Paper” (David Larbalestier, Lance Cooley, Ken Marken and Alvin Tollestrup) to form collaboration among interested National Labs, Universities and HTS vendors to develop program

• Broad Collaboration of NMR, material science and HEP application interested in >23 T at 4 K and >10 T at 20 K


Collaboration Plans

• Ongoing discussions among the National Magnet Labs and University representatives to write a proposal to DOE•Identify common ground for conductor needs•Consolidate existing data on conductor tests•Identify facilities and resources•Near term and longer term plans for magnet related conductor development and testing, magnet development

• Goal for preliminary proposal: Fall 2007


Conclusion

• MCTF made significant progress this year, largely through magnet program base support, Muons Inc. collaboration and support from MCTF/APC

• Helical cooling channel design for MANX advances • Short demonstration HCC magnet will be built and

tested with support from Muons Inc. and MCTF/APC• HTS conductor studies continue at Fermilab (and

elsewhere) on a range of materials, as a function of field, field angle, temperature

• Paper studies of High Field Solenoids show feasibility and difficulties in building magnets beyond the 40 T range

• Plans for a National Program for HTS High Field Magnets have begun

mctf hardware development plans

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