Undulator Development R&D Plan

1 BROOKHAVEN SCIENCE ASSOCIATES

Undulator Development R&D Plan

Toshi Tanabe

George Rakowsky, John Skaritka, Steve Hulbert,Sam Krinsky, Timur Shaftan and Other NSLS2 Staffs

NSLS-II

NSLS-II Accelerator Systems Advisory Committee 2007/04/23-24


Outline

1) Permanent Magnet Damping Wiggler2) Elliptically Polarized Undulator (EPU)3) 3 Pole Wiggler4) Cryo-Permanent Magnet Undulator (CPMU)

Cold Measurement System Cold Gas Refrigeration System New Magnet / Pole Materials New Gap Separation Mechanism

5) Superconducting Insertion Devices SCU, SCW and SEPU High Temperature Superconductor (HTS)

6) Undulator Laboratory


1) PM-Damping Wiggler

•W100 •W80

• CDR DW (w=100mm, Gap=15mm)• Br=1.35T• Integral of B2=0.1459 T2.m (90.0% of ideal 1.8T sinusoidal field=0.162 T2.m)• Keff/ = 2.71 mrad

• New Design with side magnets (w=80mm, Gap=12mm)• Br=1.30T• Integral of B2=0.1334 T2.m (103% of ideal 1.8T sinusoidal field=0.1296 T2.m)• Keff / = 2.32 mrad

Side Magnets


Effect of Pole Width in Dynamic Aperture

• 65% Pole Width=52mm (Br=1.32)[Horizontal Field Profile]

-15 -10 -5 0 5 10 15-0.035

-0.03

-0.025

-0.02

-0.015

-0.01

-0.005

0

0.005DW field: By(x)

By(x), T

1->13th harm. fit

absolute error

-15 -10 -5 0 5 10 15-0.035

-0.03

-0.025

-0.02

-0.015

-0.01

-0.005

0


By(x), T

1->13th harm. fit

absolute error

kx=0.0026 kx=0.0058

• Pole Width=80mm (Br=1.30)

• 45% Pole Width=36mm (Br=1.40)

-15 -10 -5 0 5 10 15-0.035

-0.03

-0.025

-0.02

-0.015

-0.01

-0.005

0


By(x), T

1->13th harm. fit

absolute error

kx=0.017


Tracking Result

•Up to 13th longitudinal harmonics are included

-40 -30 -20 -10 0 10 20 30 400

1

2

3

4

5

6

7

8

9DA for compensated DW, no errors

Wide poles

Narrow poles

45%


2) EPU Comparison

• Apple-II v.s. HiSOR EPU

dzdzyx

BdzBdz

yx

BdzB

By

yx

xyx

'/

''/

')(

12/

second order kicks (Elleaume, EPAC 1992):


Radia Kick Map (Helical Mode)

• Apple-II • HiSOR[Vertical Kick]


Radia Kick Map (Helical Mode)

• Apple-II • HiSOR[Horizontal Kick]

•More ellaborate trackings will be conducted


3) 3 Pole Wiggler

16mm 17.5mm

Main Magnets: 120 x 44. x 90 mm

Center Pole: 120 x 20 x 65 mm

End Poles: 95 x 40 x 86 mm

•Br=1.35T

•Permendur Center Pole

•Soft Iron (1006) Side Poles

•Rectangular Magnets

S [mm]

• Requirements:• More than 2 mrad of radiation fan above 1T field• Use narrow gap dipole (35 mm Gap) chamber • Fixed gap and removable from one side of the chamber• Placed next to a BM Cross talk issues are being investigated (3D model)

•Preliminary Magnetic Design


By, Angle, Trajectory

•Red lines show the fanning angle required by the users


4) CPMU

•SPring-8 (Courtesy of T.Tanaka) •ESRF (Elletra Workshop 06)

•Japanese/European Efforts on Cold Measurement System


Our Approach

• Detachable system from side opening Dedicated measurement chamber (SP8/ESRF)

• Adaptable positioning system using feed back from laser tracker for Hall probe

• Hope to adapt the stretched wire system design by ESRF

• Stable square shape pulse generator with a flat-top longer than 15msec has to be developed for pulsed wire measurement with 3.5m device


New Materials

•W. Swift and M. Mathur

IEEE Trans. Mag. Vol.10, No.2 (1974)

•Crystalized Dysprosium Pole• Very high saturation flux density ~ 3.5T

Vanadium permendur ~ 2.3TSoft iron ~ 2.1T

B [T]

3.0

H [105 A/m]

•Latest PrFeB Magnet • New CR53 from Hitachi Metal

Values at RT P-53CR(PrFeB)

42AH(NdFeB)

Br [T] 1.35 1.28 (Min)

Hcb [kA/m] 1032 970

Hcj [kA/m] 1361 1909

(BH)max [kJ/m3] 349 318


New In-vacuum Gap Separation Mechanism

Linear motors drive the outer cage.

Vacuum chamber

Rail


Impproved Cold Gas Refrigeration System

• Triple stage cryocoolers to cover wide temperature range

• Linear motor to pump the gas instead of compressed air activated cylinder

• It will be tested to cool down the LDRD funded HTS sextupole proto type (shown on the right)


5) Superconducting Insertion Devices

• Low Temperature Superconducting Undulator/ Wiggler • Test APC-NbTi wire

• Low Temperature Superconducting EPU• Design study, especially winding technique

• High Temperature SC Devices• Rapid conductor development in the industry• New type such as coated conductor and thin film available More design flexibility• Once the conductor exceeds the necessary performance level, it will be very

promising candidates for future IDs


Insertion Device Laboratory

• Class 10000 Temperature Controlled Semi-Clean Room for IVU Measurement

• Metalic dust is very hard to remove after assembly.• Prevent bugs from entering hard-to-reach area.• 22 °C± 0.2 °C or tighter (Cf. LCLS MMF: 20 °C± 0.1 °C)• Low vibration required by pulsed wire measurement

• Standard ID measurement setups• 6-7 m Hall probe bench• Stretched / pulsed wire system (3-4m)

• Cold Measurement Apparatus• Dedicated cold measurement system with independent refrigerator• Hall probe calibration setup in controlled temperature

• Winding Machines for SC device development• CAD to CAM system for yoke fabrication


Summary

• DW may require further refinement to reduce the impact on the ring.• How much of the longitudinal harmonics can be tolerated?

• More rigorous trackings will determine optimal structure of EPU for NSLS-II.• 3 pole wiggler will be conventional PM device, however;

• Magnetic interaction with adjacent magnets should be taken into account• Residural dispersion due to asymmetric beta function at the location has be to

minimized.• Development of accurate cold field meamsurement system is essential for

successful operation of CPMU.• New materials to be developed for higher performance• New gap separation mechanism to simplify the structure

• SC insertion devices planned for NSLS-II require further R&Ds.• Undulator Laboratory must have state-of-the-art measurement system to be

competitive for next 20 years of operation.

Undulator Development R&D Plan

Documents

Transcript of Undulator Development R&D Plan