S. Gourlay 7/19/01 T2 Working Group Summary T2 Working Group Summary Magnet Technology: Permanent Magnets, Superconducting Magnets, Power Supplies Conveners: Stephen Gourlay and Vladimir Kashikhin Organizing Committee Contacts: J. Strait and G. Dugan

S. Gourlay 7/19/01 T2 Working Group Summary Outline T2 Working Group A glance at recent progress Highlights –Permanent Magnets –Superconducting Collider Magnets Review of US Magnet Programs Summary

S. Gourlay 7/19/01 T2 Working Group Summary Organization Superferric Magnets Very High Field Magnets Collider Magnets Permanent Magnets and Applications Magnets for the Muon Collider Detector Magnets Magnetic Measurements High Gradient Quads Magnet R&D Issues for the Future Quench Protection Bill Foster Shlomo Caspi Sasha Zlobin Bill Fowler Mike Green Katherine Pacha Hank Glass Mike Lamm Ramesh Gupta A. McInturff Topics Coordinators

S. Gourlay 7/19/01 T2 Working Group Summary Participants S. Caspi, S. Gourlay, M. Green, G. Sabbi Berkeley National Laboratory R. Gupta, R. Palmer, B. Parker, S. Peggs, P. Wanderer, R. Weggel Brookhaven National Laboratory Rob Van Weelderen CERN G. Dugan, A. Mikhailichenko, M. Tigner Cornell R. Diebold Diebold Consulting B. Strauss Department of Energy P. Bauer, G.W. Foster, W. Fowler, H. Glass, H. Jostlein, V. Kashikhin, M. Lamm, P. Limon, E. Malamud, J.-F. Ostiguy, I. Terechkine, R. Yamada, V. Yarba, A. Zlobin Fermi National Laboratory K. Pacha U. Iowa M. Wake KEK M. Kumada NIRS D. Walz SLAC P. McIntyre, A. McInturff, A. Sattarov Texas A&M University

S. Gourlay 7/19/01 T2 Working Group Summary Recent Progress Significant progress in magnet development since Snowmass ’96. –Conductor Nb 3 Sn and HTS –Magnets FNAL Transmission line Permanent magnets for beam transfer and storage rings Increased Nb 3 Sn magnet development (~15 T) –Fermilab vertical magnet test facility for model magnets RHIC industrial procurement – provides cost basis LHC IR Quadrupole R&D and Pre-production

S. Gourlay 7/19/01 T2 Working Group Summary Superconducting Magnets

S. Gourlay 7/19/01 T2 Working Group Summary Permanent Magnets New materials –Sm 2 Co 17 –Nd 2 Fe 14 B Applications –LC Adjustable permanent magnet quadrupoles –VLHC Injection line, correctors, Lambertsons 300 T/m PM quadrupoles for IR’s 4 Tesla PM or hybrid accelerator dipole –TESLA Damping ring magnets –Wigglers Higher Fields

S. Gourlay 7/19/01 T2 Working Group Summary Permanent Magnets R&D Trends –Accelerator Magnets – long term thermal and radiation stability –Active and passive correction systems Hybrids (PM + SC) –Adjustable quadrupoles - high magnetic center stability Mechanical systems to provide adjustability –Cost optimization - accelerator magnets Competition for conventional magnets –High fields - multipole fields comparable with SC –Reduced capital and operational costs

S. Gourlay 7/19/01 T2 Working Group Summary Superconducting Magnets Conductor Performance Performance/Cost/Industrial Capacity NbTi –Hc 2 is too low to benefit much from further increases in J c –Cost is probably at a minimum Nb 3 Sn –Factor of 3 improvement in J c in past 5 years –DOE sponsored conductor development program is showing good progress after first year. Funding for next year looks promising. HTS –Very expensive and still needs vast improvement in performance

S. Gourlay 7/19/01 T2 Working Group Summary Collider Magnets Majority of discussion was on magnets for large colliders –Significant cost component –Options Low field (superferric) Medium field - RHIC scale-down plus others Orphan Option? High field

S. Gourlay 7/19/01 T2 Working Group Summary Collider Magnets Superferric (2 – 3 Tesla) Fermilab Transmission Line Magnet Used for VLHC Design Report (Bmax ~ 2T) Texas Accelerator Center Magnet Cold iron, 3T, Multiple current supplies Simple and low power cryogenics Standard cryogenics (more complex) But higher dynamic range

S. Gourlay 7/19/01 T2 Working Group Summary Collider Magnets Dipoles (4 – 15 Tesla) Many Options Conductor –NbTi and Nb 3 Sn Issues –Cost (aperture, length, complexity) –Synchrotron radiation load Beam screens vs photon stops –Magnetization effects –Dynamic range, multiple power supplies –Quench Protection –Magnetic measurements Stretch-wire alignment and strength IR Quads Technically challenging Large aperture –Field quality, heat load High gradient –> 300 T/m High heat loads –600 W/side VLHC-1 Mechanical alignment and stability Valuable experience with LHC quads HTS Candidate?

S. Gourlay 7/19/01 T2 Working Group Summary US Magnet Programs BNL, LBNL, FNAL, Texas A&M –Basic geometries Cos-theta Block Common coil (Block)

S. Gourlay 7/19/01 T2 Working Group Summary US Magnet Programs Brookhaven National Laboratory Development of HTS-based magnets –Neutrino factory magnets –IR quads

S. Gourlay 7/19/01 T2 Working Group Summary US Magnet Programs Berkeley National Laboratory High field, Nb 3 Sn –Common Coil –Conductor and cable development Medium field VLHC design Bi-2212 Cable 14.7 T Common Coil

S. Gourlay 7/19/01 T2 Working Group Summary US Magnet Programs Fermi National Laboratory High Gradient Quads for LHC Permanent Magnets –Quads for a LC Superferric –Transmission Line Magnet High field, Nb 3 Sn –VLHC magnets 11 T common coil and cos-theta

S. Gourlay 7/19/01 T2 Working Group Summary US Magnet Programs Texas A&M University High field (12 T) –Small bore –Stress-management for high fields –6.7 T NbTi prototype of 12T block magnet –“TeV Tripler” design studies

S. Gourlay 7/19/01 T2 Working Group Summary Summary More magnet options are now available –These options should be evaluated in terms of achieving the lowest cost machine –They offer flexibility in determining other important parameters Real cost effective applications can only be realized using an integrated approach and a more aggressive R&D program –Requires enhanced communication between magnet designers and accelerator physicists –A cost model that can be used to focus and evaluate technology options Expand in-depth Design Report work to other magnet options –Resources and effort required to bring the existing magnet technology options to a point where they can be reliably evaluated and considered for use in a collider design do not currently exist