S. Gourlay 7/19/01 T2 Working Group Summary T2 Working Group Summary Magnet Technology: Permanent Magnets, Superconducting Magnets, Power Supplies Conveners:

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

T2 Working Group SummaryMagnet Technology: Permanent Magnets, Superconducting Magnets, Power Supplies

Conveners:

Stephen Gourlay and Vladimir Kashikhin

Organizing Committee Contacts:

J. Strait and G. Dugan


Outline

• T2 Working Group

• A glance at recent progress

• Highlights– Permanent Magnets– Superconducting Collider Magnets

• Review of US Magnet Programs

• 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


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


Recent Progress

Significant progress in magnet development since Snowmass ’96.

– Conductor• Nb3Sn and HTS

– Magnets• FNAL Transmission line• Permanent magnets for beam transfer and storage rings• Increased Nb3Sn 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


Superconducting Magnets

FNAL Superferric Transmission line 2 NbTiTAC Superferric Block 3 NbTi

RHIC Cos 4.5 NbTiTexas A&M Block 6.6 NbTiSSC 50 mm Cos 7.5 NbTi

LHC Cos 7.8 NbTiLHC (1.8K) Cos 10.1 NbTiTevatron Cos 5.5 NbTiU. Twente Cos 11.5 Nb3SnLBNL D20 Cos 12.8 Nb3Sn

LBNL D20 (1.8K) Cos 13.5 Nb3SnLBNL RD-3 Common Coil 14.7 Nb3Sn

Dipole Magnet Max Field (T) MaterialCoil Geometry


Permanent Magnets

• New materials – Sm2Co17

– Nd2Fe14B

• 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


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


Superconducting Magnets

Conductor PerformancePerformance/Cost/Industrial Capacity

• NbTi– Hc2 is too low to benefit much from further increases in Jc

– Cost is probably at a minimum

• Nb3Sn– Factor of 3 improvement in Jc 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


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


Collider Magnets

Superferric (2 – 3 Tesla)

Fermilab Transmission Line MagnetUsed for VLHC Design Report (Bmax ~ 2T)

Texas Accelerator Center MagnetCold iron, 3T, Multiple current supplies

230

660 REF.

SUPERCONDUCTINGTRANSMISSION LINE

100 kA RETURN BUS

CRYOPIPES

VACUUMCHAMBER

Support Tube /Vacuum Jacket

Simple and low power cryogenics

Standard cryogenics (more complex) But higher dynamic range


Collider Magnets

Dipoles (4 – 15 Tesla)Many Options

• Conductor – NbTi and Nb3Sn

• 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?


US Magnet Programs

• BNL, LBNL, FNAL, Texas A&M– Basic geometries

• Cos-theta• Block• Common coil (Block)

•


US Magnet Programs

Brookhaven National Laboratory

• Development of HTS-based magnets– Neutrino factory magnets– IR quads


US Magnet Programs

Berkeley National Laboratory

• High field, Nb3Sn

– Common Coil– Conductor and cable development

• Medium field VLHC design

Bi-2212 Cable14.7 T Common Coil


US Magnet Programs

Fermi National Laboratory

• High Gradient Quads for LHC

• Permanent Magnets– Quads for a LC

• Superferric– Transmission Line Magnet

• High field, Nb3Sn– VLHC magnets

• 11 T common coil and cos-theta


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

x3.6151

0.5770

1"xc yc R

0.5242 1.9108 0.0787 xc yc R2.2728 2.2224 0.2211

0.6030 extra space=0.01

xc yc R0.6817 1.6452 0.0787 x y

2.8277 1.5665

1.9895 space= 0.013space= 0.013+0.1mm

0.7468

space=0.009

str.gauge+mica+spacer=0.051extra space=0.01

str.gauge+mica=0.025


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

Documents

S. Gourlay 7/19/01 T2 Working Group Summary T2 Working Group Summary Magnet Technology: Permanent Magnets, Superconducting Magnets, Power Supplies Conveners: