Superconducting Magnets at Fermilab

1
Superconducting Magnets at Fermilab

• Superconducting accelerator magnet development
  and fabrication at Fermilab has a long history of
  success oriented toward practical magnets for
  real accelerators.
• The Fermilab program is aimed at the most
  important issues of superconducting accelerator
  magnet development.
• Superconducting magnet design, production and
  testing fits the mission of the Laboratory and
  the present U.S. HEP program.
• It supports the Fermilab accelerators.
• It is an important part of the U.S. HEP program
  at the LHC.
• The RD program supports the U.S. high-energy
  physics plan for the future as presented in the
  recent HEPAP Subpanel report.
• Our RD is important for upgrades to strengthen
  the LHC HEP experiments and U.S. accelerator
  physics capability.
• Magnet RD now is necessary to be able to make a
  decision that will permit construction of a VLHC
  within 20 years.

2
Outline of the Presentations

• Overview
• History, Motivations, Present Programs, Parameter
  Choices, Personnel, Future Directions, Cost
  History Projections, Summary
• Magnet Technical Programs Achievements
• Tevatron, LHC, High-Field Magnets, Superferric
  Magnets
• Superconducting Materials RD and Testing
• Infrastructure (with a tour)
• Materials RD, Model Magnet RD, Production,
  Testing
• Plans for the Future
• Second-Generation LHC Insertions, VLHC Magnets

3
History

• Fermilab has a long history of SC magnet
  development oriented toward practical magnets for
  real accelerators
• Tevatron
• First superconducting synchrotron magnets
  designed built (almost exclusively at
  Fermilab), 1973-1983.
• First collider operation, 1985
• Tevatron Low Beta Quadrupoles, installed
  operating, 1990
• SSC Dipole RD and fabrication, 13 dipoles
  delivered, 1992
• LHC IR Quadrupole development and fabrication,
  1996 - 2004
• Starting Nb3Sn accelerator magnet development,
  1999
• VLHC
• LHC 2nd generation Quads
• Designing for construction is intrinsic to the
  Fermilab culture. Striking a balance between RD
  and construction is important for the health and
  vigor of the Fermilab program.

4
Motivations

• Maintenance Improvement of the Tevatron
• Fermilab must maintain the human and physical
  resources to keep the Tevatron working, and
  upgrade it as necessary.
• By having a first-class RD program, we attract
  top-notch scientists engineers, and keep our
  capabilities sharp.
• Staying at the Frontier of SC Magnet Technology
  for HEP
• The U.S. LHC Accelerator Project has made
  important contributions to the LHC.
• The insertion quads design, development,
  fabrication and test at Fermilab is the flagship
  of that program.
• The LHC Accelerator Research Program will greatly
  strengthen U.S HEP at LHC.
• The 2nd-generation IR quadrupoles from Nb3Sn will
  be the flagship of that program, and will advance
  U.S. Nb3Sn magnet development.
• Keeping Our Options Open for the Future.
• HEP will almost certainly need to move to the
  next energy scale, 10 TeV, or more. The only
  sure way to do this is a hadron collider, and the
  most likely location is in the U.S.

5
The Magnet RD Program

• Two paths to successful Nb3Sn magnets for
  accelerators.
• Cosine-Q Nb3Sn dipoles and quadrupoles
• Flexibility - multiple applications
• Common-coil dipoles
• Possible react wind - may be a money-saver for
  the VLHC
• Single-layer design solves the most serious
  problems of the common-coil concept
• Supporting RD
• SC materials
• Strand and cable development and testing
• Fast-response coil RD
• Pancake-coil magnets

6
Recent Program Changes

• The superferric magnet program is being closed
  down
• Limited resources has forced us to close this
  successful RD program
• Motivation is a staged concept of the VLHC
• Attempting to bring this program to a soft
  landing by carefully documenting its
  accomplishments

7
High-Field Cosine Q Designs

• The cos-q designs are flexible and have many
  applications
• Single and double aperture, dipoles and
  quadrupoles, warm and cold iron
• A continuation of Fermilab cos-q dipoles,
  low-beta quads and LHC quadrupoles.
• A familiar design at Fermilab using new (to us)
  materials.
• Can be extended naturally to 2nd generation LHC
  quads
• Up to now, restricted to wind react method with
  Nb3Sn

8
High-Field Common-Coil Design

• The Common-Coil design is intrinsically 2-in-1
• The gentle bends may permit react wind methods
  with existing materials
• Possibly reducing the cost of high-field magnets
• It may be have applications with HTS and MgB2,
  etc.
• The Fermilab design is wound directly into a
  stress-management collar structure
• Designed to deal with huge forces intrinsic to
  common coil
• Production innovations may reduce the cost

9
Superferric Magnet RD

• Design driven by the staged VLHC concept
• 2-in-1 warm iron 2T bend field
• 100kA Transmission Line
• Alternating gradient, 65m Length
• Warm Vacuum System
• Bringing the first phase of the RD to a smooth
  conclusion
• Finishing the active and interesting RD efforts
• 100 kA power supply leads
• Assembly welding techniques
• Operation of model magnets
• Publish the results
• Put work and infrastructure into a state that can
  be restarted if desired

10
Materials RD

• Excellent infrastructure for strand development
  and testing
• Ovens, SEM, optical microscope, Teslatron
• Cabling machine, cable tests at NHMFL
• Participates in the national Nb3Sn RD program
• Collaborating in Phase II SBIR for more flexible
  Nb3Sn cable
• Working on other materials, too
• Ceramic cloth and binders
• Infrastructure includes Instrons, strain gauges,
  etc.

11
Generic Development Test

• The Racetrack Coil effort is a common-coil magnet
  with flat coils.
• Primarily used to investigate procedures and
  materials needed for react wind Nb3Sn
• The simplified coils allowed us to start react
  wind RD earlier
• Permits fast turn-around on model fabrication and
  we are investigating ways to make it faster

12
Field Strength

• Although very-high-field magnets will be needed
  for some applications, we have concluded that
  very-high magnetic field is not optimum for a
  very-high-energy collider.
• Colliders with very-high-field magnets cost more.
• Synchrotron radiation limits the energy and
  luminosity for high-energy, high-field colliders.
• Large-circumference rings (moderate field) may
  permit the use of photon stops, which could
  remove many of the limits due to synchrotron
  radiation.
• We believe that 12 T is a realistic goal, and
  optimum for the total cost and performance of a
  VLHC with E ? 100 TeV.

13
Motivation for a Strong Program Now

• Experience indicates that it is not too early to
  start
• An LHC IR quad upgrade should be ready in
  2013-2014, which means prototypes should be
  tested by 2010.
• A construction start on a VLHC is part of the
  HEPAP Subpanel 20-year plan.
• Technical issues need to be resolved much earlier
• The penalties for not being technically ready are
  severe
• Its clear there are technical challenges in
  Nb3Sn high-field magnets.
• Now is a good time to increase the RD effort
• Experienced people are coming off the U.S. LHC
  project and can make significant contributions to
  the magnet RD
• Now is the right time for the U.S. to take the
  world-wide lead in magnet RD.
• Investment in SC accelerator magnet RD is
  decreasing outside the U.S., partially because of
  LHC construction.

14
Experience indicates its not too early
15
Effort Distribution, Average for 2002

• Scientists Engineers
  Drafters Techs
• LHC Insertions 2.7 7.0 1.6
  15.5
• LHC Project 0.6 1.01.8 CS --
  --
• Magnet RD 3.8 2 stdnts 9.3 3.0
  5.5
• Tevatron 1 lt1 lt1 3
• Total (w/o project) 9.5 17.0 5.0
  24.0
• By comparison
• LHC (FY1999) 7.2 15.7 13.0
  15.4
• Recent and planned personnel activity in Magnet
  RD
• In recent years, two experienced engineers and
  one scientist went to linear collider and one
  engineering physicist and one scientist left
  Fermilab.
• We budgeted this year for one new postdoc, one
  engineer in materials RD, and two replacement
  students.

16
Future Directions

• The Fermilab program will remain focused on the
  important and primary goals
• The cos-q dipole program will morph into the
  LHC-ARP 2nd generation quadrupole program over
  the next three years, in collaboration with LBNL
  and BNL
• The stress-management common-coil approach will
  be strengthened as long as it appears useful for
  VLHC
• We will start to make long magnets (gt10 m) of the
  2nd generation quad and the common coil in 2009
• The racetrack coil effort and the materials RD
  work support the material and engineering needs
  of the Fermilab and national programs, and will
  continue

17
Superconducting Magnet Budgets
18
Superconducting Magnet Budgets
19
What This Program Accomplishes

• By 2010 we will have accomplished all of the
  goals outlined in the 2002 HEPAP Subpanel Report
• Strengthened our magnet team for Tevatron-based
  HEP
• Developed and brought to production readiness a
  2nd-generation IR quadrupole to improve the LHC
  HEP program
• Developed at least one magnet technology suitable
  for a high-field VLHC
• If we succeed in both designs, we will have the
  knowledge to help choose which is better
• We will have the information to make accurate
  cost and performance estimates and help choose a
  VLHC concept from among the many options
  Staged? Low-, Moderate-, or High-field?
• We will be able to make a timely choice and turn
  up the relevant program to industrialize the VLHC
  magnets by 2015
• All of this with a program that has approximately
  the same level of funding as our present program