Magnet R

1
Magnet RD through the MCTF
Michael Lamm
2
MCTF Magnet Effort

• Support specific magnet project for 6D Cooling
  Demonstration
• Helical Cooling Channels and Matching Sections
• Longer Term Magnet RD
• 50 T Solenoid
• Next generation Helical Solenoid (future Muons
  Inc SBIR)
• Collider and IR magnets?
• Provide Coordination for Muon Magnet Program for
  Fermilab Muon Experiments
• Interface with AP and Detector groups
• Coordinate activities with other magnet
  laboratories (BNL, FNAL, LBNL, NHMFL, Muons Inc.)
• Called out in MCTF charge and primary RD focus

3
FNAL Superconducting Magnet Program

• All phases of accelerator magnet development,
  incl. superconductor RD test and support
• Long history of SC magnets (Tevatron, SSC,
  Fermilab/LHC IR quads)
• Present primary focus is on Nb3Sn Quadrupoles for
  LHC IR upgrade, as part of LARP, but also, HINS,
  ILC, Muon Collider and Tevatron support
• Projects such as Muon Magnets RD depends heavily
  on Fermilab base support for SC Magnet RD
• Provides for infrastructure support
• Provides salary and MS support for RD beyond
  project scope

4
Helical Cooling Channel

• Cooling Channels proposed by Muons Inc for MANX
  experiment. Time scale for demonstration 2010
• Solenoid, with superimposed helical quad/dipole
  filled with low Z material can reduce 6D
  emittance
• Recent work by Vl. and Va. Kashikhin K. Yonehara
  present two practical designs for MANX muon
  cooling demonstration. (see Yonehara talk)
• SBIR have been submitted to carry this program to
  cooling channels suitable for full scale muon
  collider

5
Plan for Production Helical Solenoid
Outlined in MCTF proposalbased on a proposed
level of support..

• FY06
• Tracking studies
• Two designs under consideration
• FY07
• Complete Design Comparison/Design Decision
• Build engineering model/demonstration coil to
  test concept
• Design Specifications, conceptual design, and
  Prototype plan presented in Sept 2007 report
• FY08
• Complete Engineering Design
• Bids placed, prototype built in Industry
• Test (in sections) at Fermilab Magnet Test
  Facility
• Preproduction Review
• FY09
• Production Magnets order placed
• Installation in Muon Cooling Experiment as
  available through 2010

6
Large Bore Option
SEE ASC 2006 Publication Kashikhin et al, 1LL07
7
Helical Solenoid
The solenoid consists of a number of ring coils
shifted in the transverse plane such that the
coil centers follow the helical beam orbit. The
current in the rings changes along the channel to
obtain the longitudinal field gradients.
One can see that the optimum gradient for the
helical solenoid is -0.8 T/m, corresponding to a
period of 1.6 m.
8
Concept Decision in FY07

• Issues for making designs
• Heavily dependent on (un)certainty about the
  design of the experiment
• Small bore design is modular, less expensive to
  build and test. Large bore design is easier to
  adapt once built.
• Conceptual design work on matching sections
• Resource loaded schedule for magnet system
  including mechanical design, cryostat design,
  quench protection, etc. to estimate labor/MS for
  each design

General consensus is that small bore option is
the preferred solution
9
Design Tasks in FY07

• Mechanical Designs for coils structure (small
  bore segmented solenoid option)
• 5cm multiturn stack of hardway bend NbTi cable
  (LHC IR), potted? shrink cylinder for radial
  forces
• Mechanical support for longitudinal compression
• Sets of coils locked into transverse tracks to
  withstand expected 300kN longitudinal (end) and
  200kN transverse restoring force
• Helium vessel 4 meter long x 1 meter diameter
  cylinder
• Goal to build demonstration coil (s) support
  this year
• Electrical design- linear longitudinal decrease
  in field accomplished by
• Separate PS (5-10 kA systems, each with separate
  controls etc..) or segmentation by cold diodes
• Nested PS (multi small current leads)
• Coil density (reduces modularity)

10
Design Tasks in FY07

• Cryo-issues
• Coils beam space in same Helium volume
• How does design match MTA cryo plant?
• Expected max static heat load ten Watts.. No
  appreciable beam issues.. Multiple power leads
  (if needed) have to be laid out
• Lots of LHe dead space.. Need displacer system to
  reduce helium volume
• Quench Protection .. 4 MJ stored energy
• Coils will be coupled
• Dependent on coil powering
• Regardless, adjacent segments are magnetically
  coupled
• We have experience with this LHC cable should be
  easy to model (MIITS, quench velocity etc..)
• Is external extraction circuit or heaters needed?

11
Superconducting Coil Test Facility
Superconducting coils can be tested using
Vertical Dewar at FNAL Magnet Test Facility Test
Stand with 30 kA power supply, quench protection
and computer control systems. Stand has 600 mm
inner bore diameter.
Number of circular sections
3 Middle section
removable Inner
section diameter
400 mm Inner coil diameter
420 mm Outer section
diameter
500 mm Center section shift in transverse Y
direction 60 mm Coil length along Z
50 mm Coil
total current
262 kA Conductor current
10.5 kA Coil
number of turns
25 Force in Z direction
353 kN Force in Y
direction (middle coil) 234
kN
Helical Solenoid Forces Section N Fx,
kN Fy, kN Fz, kN 1
-185 -63 304 36
74 -11
-8 73 -49
18 -81 Coils shifted 55.5 mm in
radial direction, Frmax196 kN
12
Three Coils Set
Coil centers X, mm Y, mm Z,
mm 0 255
0 55.2 249 55.6 107.8
231.1 111.1
Quench Protection/Characterization -use energy
extraction circuit -instrument with voltage
taps -middle coil instrumented with spot
heaters Magnetic Field measurements -Hall Probes
13
How this is accomplished in FY07

• Yonehara/Kashikhin/Kashikhin continue to validate
  two designs matching section
• Practical details of how this magnet would be
  designed. (ie. Cable vs strands, mechanical
  support, alignment, cryostat)
• Additional 0.5 FTE of existing staff ?
• Contract designer
• Work with TD/Test and Instr. Dept. on testing
  plans
• Coil(s) can be tested in vertical dewar
• Cable from LHC IR quads is available but need to
  purchase all other materials for demonstration
  coils

Progress beyond paper studies requires additional
beyond base budget
14
50 T Solenoid

• See talks by Palmer and Kahn
• Proposed for end of cooling channel for final
  emittances
• 50 T DC, 30 mm aperture, 1-2 m length
• Superconducting for manageable power reqs
• HTS or HTS/Nb3Sn/NbTi hybrid
• Beyond present capabilities (has never been
  attempted)
• Proposals to built 25-30 T HTS solenoids
• Conceptual design studies performed with Muons
  Inc. in collaboration with BNL.

15
Interest in HTS for high field solenoids

• NHMFL has developed 5 T HTS insert, for 25T
  solenoids
• Muons Inc has pending SBIRs on HTS application
  to magnet design
• Fermilab, BNL and LBNL experience on conductor
  and small coils
• 2212 day workshop organized by Tollestrup
  Larbalestier November 6, 2006

16
Outline for MCTF 50 T Solenoid

• Up to and Including FY06
• Significant work done by Muons Inc. on Magnet
  Concept
• Muons Inc supported work on HTS materials at
  Fermilab
• Prepare plan for Sept 2006 report
• FY07
• Focus on Material Studies, available materials,
  relation to magnet design
• 1-5 T insert(s) suitable for SC RD lab 16 T or
  17 T Teslatron or BNL SC conductor test facility
• Present Status of Feasibility Study and
  Conceptual Design as part of Sept 2007 report
• FY08
• Material Choice(s)
• Develop Measurement equipment for Feasibility
  Study
• Lower field prototype to study Design Feasibility
  ?
• Engineering Design???
• FY09
• ?

17
2007 Effort on 50 T RD

• Evaluation of HTS Materials
• BSCCO 2212 wires/cable
• We have requested samples of BSCCO and YBCO tapes
  from conductor vendors
• Mechanical/electrical probe design and
  construction
• Tensile strain
• Field orientations
• HTS coil insert designs
• 1-5 T insert(s) suitable for SC RD lab 16 T or
  17 T Teslatron
• Investigate possible collaborations/cooperations
  with NHMFL, BNL, Muons Inc and others.to develop
  long term strategy

18
Other magnet related work

• MCTF Proposal calls for magnet effort at LBNL on
  Collider Dipoles
• Design studies for muon collider dipole (open
  midplane vs. absorber )
• Open midplane dipole made from existing Nb3Sn
  coils
• Unlikely to perform studies without additional
  support

Gupta et al Optimization of Open Midplane Dipole
Design for LHC IR Upgrade PAC07
19
Magnet Conclude

• Fermilab continues to work with Muons Inc to make
  Helical solenoid with 2010 delivery date
• In FY07 need to develop detailed plan which leads
  to delivery of helical solenoid.
• 50 T Solenoid with FNAL, BNL and Muons Inc.
  Work focused on materials for first year. Goal
  to make 1-5 T insert suitable for 15 T Teslatron
  with 77 mm bore.
• FY07 will be a year of studying HTS materials,
  building a collaboration to coordinate long term
  effort

Need requested additional resources to make
progress past paper, especially if Helical Cooing
Channel required in 2010