Super-conducting damping wigglers; specifications and solutions

December 1, 2009

Remo Maccaferri

CLIC Technical Committee

C L I CC L I COriginal Program

Two wiggler short-prototypes2.5T, 5cm period, built and currently

tested by BINP2.8T, 4cm period, designed by CERN/Un.

Karlsruhe

Short prototypes built and magnetically tested (at least one by CDR 2010))

2012 Prototype Installed in a storage ring (ANKA, CESR-TA, ATF) for beam measurements (IBS/wiggler dominated regime)

C L I CC L I C

Parameters BINP CERN

Bpeak [T] 2.5 2.8

λW [mm] 50 40

Beam aperture full gap [mm] 12 12

Conductor type Nb-Ti Nb3-Sn

Operating temperature [K] 4.2 4.2

Original Parameters

C L I CC L I C

Wigglers beam size

BINP Permanent Magnets

BINP

NbTi

CERN Nb3Sn

C L I CC L I C

0

0.5

1

1.5

2

2.5

3

3.5

4

10 12 14 16 18 20

B (peak) Gap size

Gap [mm]

B[T]

C L I CC L I C

Armco vs Permendur

0.00E+00

2.00E+04

4.00E+04

6.00E+04

8.00E+04

1.00E+05

-4 -3 -2 -1 0

cm

B [

Gau

ss ]

B armco

B Permen.

B midplane armco vs permendur

-4.00E+04-3.00E+04-2.00E+04-1.00E+040.00E+001.00E+042.00E+043.00E+044.00E+04

-4 -3 -2 -1 0

cm

Gau

ss By armco

Bypermendur

ARMCO vs PERMENDUR

Vanadium Permendur:

Bsat > 2.3 T

Soft magnetic alloy of 2% vanadium, 49%

cobalt and 49% iron

C L I CC L I C

Permanent magnets?

Sintered magnets: Sm2 Co17

(VACOMAX 240)

Bmax 1.2 T

- To build a suitable wiggler we need pole concentrators

- We can use permendur but the maximum pole field will not be more than 2.3 T

- With a gap of 14 mm the peak field on the mid plane will be in the order of 1.1 T !

ADVANTAGE: No Cryogenics !

C L I CC L I C Hybrid solution?

Could not

succeed….

C L I CC L I CNb-Ti Nb3-Sn

C L I CC L I CNb-Ti Nb3-Sn

“ sacrificing Nb3Sn current density in favor of temperature margin can provide very good heat transfer capacity: more than 1 order of magnitude bigger than Nb-Ti”

Phys. Rev. ST Accel. Beams 11, 082401 (2008)

Heat load capabilities

C L I CC L I CNb-Ti/Nb3-Sn Wigglers optimization

C L I CC L I CWigglers Design

IRON YOKE COIL FGP SPACEREND COILS

END IRON YOKE AND

BOLT

COIL CORRECTION

CERN

BINP

C L I CC L I CBINP short-prototype

C L I CC L I CCERN short-prototype

C L I CC L I C

Training of the CLIC wiggler short model (2 periods 40 mm & 16mm gap)

300

400

500

600

700

800

900

1000

0 5 10 15 20 25

Quench number

Cu

rren

t [A

]

@1.9 K@ 4.2 K

@ 4.2 KafterThermalCycle

Vertical Race-track coils test

C L I CC L I CObtained Mid-plane peak field vs. current for 40 mm period and scaling for 50mm period

Mid plane peak field vs Current

0

0.5

1

1.5

2

2.5

3

0 200 400 600 800 1000

[ A ]

[ T ]

50 mm period

40 mm period

Vertical Race-track coils test

C L I CC L I C

Operating load line

C L I CC L I CVertical Race-track short model status

Modeling:- Magnetic 2D : Done (Maccaferri, Schoerling)

- Forces calculations : Done (Maccaferri, Schoerling)

- Magnetic 3D : On going (Schoerling, Bernhart)

- -Multipole analysis : To be done (Schoerling, Bernhart)

- ANSYS : To be done (Schoerling end 2009)

Prototyping (NbTi):-Mechanical design : Done(to be updated)

-Winding and impregnation: Done (J.Mazet, JC Clement)

-Cold test : Done week 41 (09)

C L I CC L I CMilestones

C L I CC L I C

Thank You !

C L I CC L I C

21

DR layout

125m

125m

39m

Y.P., 21/08/2009 CLIC meeting

C L I CC L I C

BINP Proposals

The use of another type of epoxy could be very desirable. The Araldite MY740 is probably not perfect for our tasks.

Another one is to make another test run (runs) to understand the quench behavior and to make magnet measurements.

First approach is to make short wiggler prototype without use of the GFP elements. The manufacturing of this design will start in close days. The SC cable for this short prototype is available yet.

C L I CC L I C

A cryogenic cooler SUMITOMO SRDK 408S2permits to evacuate up to 50 W power from 60 K liner.

Internal Cu liner at liquid Nitrogen temperature protects from SR

Heat-load protection