Paul Scherrer Institut - Lawrence Berkeley National Laboratory · 2017-03-30 · Gap-drive system use satellite roller screws from Rollvis (CH) to adjust wedges: - A full stroke (360°)

Wir schaffen Wissen – heute für morgen

Oct. 18, 2012PSI,

Paul Scherrer Institut

Development and fabrication of undulator U15 for SwissFEL on behalf of department of Mechanical Enginering and of group of insertion devices

Urs Ellenberger

Outline

• Overview

• Goals and specific requirements of undulator U15

• Key components of design

• Summary

Development and Fabrication of Undulator U15 for SwissFEL, Urs Ellenberger MEDSI, Shanghai 2012, October 18 Slide 2

Outline

• Overview



• Summary



Overview of main activities of PSI with its large research facilities

Main research activities:- matter and material- energy and environment- biomedical sciences

Largest user laboratory in Switzerland:- 1‘200 staff scientists and engineers- 2‘000 visiting scientists per year

SLSSwiss Light Source

SwissFEL (2016)X-ray Free Electron Laser

250 MeVinjector (2010)

Proton-accelerator

P-CancerTherapy

SINQneutron source

SμSmuon source

UCN ultracoldneutron source

1 control room forall Large Research Facilities

General specifications of SwissFEL undulator lines• Undulator line for hard X-rays from 7 Å (1.8 keV) to 1 Å (12.4 keV) with electron energies of 5.8 GeV is called Aramis

• Another undulator line for soft X-rays from 60 Å (200 eV) to 6 Å (2keV) is called Athos

• Aramis line will have 12 in-vacuum undulators with a short period of 15 mm (U15)

• Industrial based small series production for a large number of similar undulatorsfor SwissFEL:

Aramis (2016): Undulator U15, short period of 15 mm, planar design, in-vacuum

Athos (2020): Undulator UE40, period of 40 mm, Apple design for variable polarization, in-air (ex-vacuum)

• Same frame and gap drive system for both undulators to profit best from series production.

• In addition same 5-axis CAM shaft movers, same street transport design (with air cushions) and same materials to purchase (except for vacuum chambers and magnets).


Quadrupole: QFFLeff,quad=0.08 m; |kFODO |=1.88 m-2

Aramis Line

Beam DumpPavg,max=560 WPpeak,max=46 TW Vertical - 8º

U15 Undulatorsgap 3.2 – 5.5 mmλu = 15 mm; K= 1.2; LU= 60 m

9.8 m

584 m

Aramis MatchingQuad QFM:Leff=0.3 m

Aramis Light2 GW; 66 μJλ =1 (0.8) - 7 Å

5 – 20 fs; 100 Hz

483.7 m; L=2.5 mBeam Stopper

Aramis EnergyCollimator

431 m Dipoles chicaneLeff, dip. =0.5 m; 1º

CorrectorQuadrupole QFB

CorrectorSextupoleHFA

Skew Quadrupoles

BPM8

Corrector Dipole AFL(Vertical Dispersion)

Alignment Quadrupole QFUProfile monitor(Wire scanner)

608 m

ØV

acuu

m=8

mm

Dipole (AFBC3): -2.5º

557.7 m

3.75

m

SA

RC

L01

SAR

CL0

2

SAR

MA0

1

SAR

MA0

2

SAR

UN

01

SAR

UN

02

SAR

UN

03

SAR

UN

04

SAR

UN

05

SAR

UN

06

SAR

UN

07

SAR

UN

08

SAR

UN

09

SAR

UN

10

SAR

UN

11

SAR

UN

12

SAR

DI0

3

SAR

BD01

BLM

Tau Monitor

477 m 501 m

BPM16

Dipole AFBC3 (1º)

ICT

SAR

UN

13

SAR

UN

14

SAR

UN

15

SAR

UN

16SA

RU

N17

SAR

UN

18S

ARU

N19

SAR

UN

20

ICT

Switch -Yard

338 m TransverseCollimator

Pavg,max=9.5 W250 pC; 10 Hz; 3.8 GeVHorizontal - 0º

Beam Stopper(L=2.4 m)

349 mDipole (AFBC3):2º; 304 m

Athos EnergyCollimator

Quad QFD Leff=0.15m

BPM16

Dipole(AFBC3): 0.5º

SextupoleHFB

382 m2.5 – 3.4 GeV

Space for Deflecting Cavities

ØV

acuu

m=

8mm

st

arts

her

e

SATS

Y01

SATS

Y02

SATS

Y03

SATC

L01

SATD

I01

SATC

B01

SATC

B02

SATM

A01

Skew QFD

Synchrotron Port

389 m

Switch -Yard

338 m TransverseCollimator

Pavg,max=9.5 W250 pC; 10 Hz; 3.8 GeVHorizontal - 0º

Beam Stopper(L=2.4 m)

349 mDipole (AFBC3):2º; 304 m

Athos EnergyCollimator

Quad QFD Leff=0.15m

BPM16

Dipole(AFBC3): 0.5º

SextupoleHFB

382 m2.5 – 3.4 GeV

Space for Deflecting Cavities

ØV

acuu

m=

8mm

st

arts

her

e

SATS

Y01

SATS

Y02

SATS

Y03

SATC

L01

SATD

I01

SATC

B01

SATC

B02

SATM

A01

Skew QFD

Synchrotron Port

389 m

96.2 m

0.355 GeV

264.8 m

2.93 GeV

TW Cav. C-Band36 * 1.92 m

27 MV/m

QuadrupoleQFD (20 T/m)Apert 22 mm

0.15 m

Profile Monitor(wire scanner)

BPM16

Electro-Optical

Sampling

BAM

192.5 m

2.09 GeV

209.6 m

DipoleAFBC3 0.5 m2.15°

ICT

Tau Monitor

TW Cav C-Band1.92 m * 1627.5 MV/m

Skew Quadrupole

CorrectorQuadrupole(QFB) Corrector

Sextupole

HFA

LINAC 1 Bunch Compressor 2 LINAC 2

9.8 m 18.2 m

Pulsed Kicker0.5 m; 1mrad vertical

S10

CB0

1

S10

CB

02

S10

CB

03

S10

CB0

4

S10

CB0

5

S10

CB0

6

S10

CB0

7

S10

CB

08

S10

CB

09

S10

BC

01

S10

MA

01

S20

CB

01

S20

CB

02

S20

CB

03

S20

CB

04

S20

SY

01

S20

SY

02

BLM

Synchrotron Port

BPM38

Septum Magnet1.5 m; 2°

273.7 m

Corrector

Quadrupole

0 m

SkewQuadrupole

CorrectorSextupole

95.4 m

BPM 38 Profile Monitor

Undulator

0.4m, U50

ICT BAM

Electro-Optical

Sampling

Electro-opticalSampling

15.3 m

131 MeV17.4 m

66.7 m

355 MeV

81.9 m

TW Cav S-Band4.083 m16 MV/m

TW Cav S-Band4.083 m

14.5 MV/m

TW Cav X-Band0.75 m

16.89 MV/m

TD Cav S-Band0.44 m0 MV/m

TW Cav S-Band0.25 m

100 MV/m

Dipole0.1 m5.7°

Dipole0.25 m

4.2°

Dipole0.25 m

30°

Dipole0.25 m

10°

QuadrupoleQFA

0.15 m; 25 T/mApert 42 mm

WCM

SolenoidWFS

0.75 m

Laser HeaterInjector linac Booster 2 Bunch Compressor 1 Injector Diagnostic Section

QuadrupoleQFD (20 T/m)Apert 22 mm

0.15 m

38.1 m

380 MeV

SIN

EG

01+

SIN

BD01

(spe

ctro

met

er)

SIN

SB

01

SIN

SB

02

SIN

LH01

SIN

LH02

SIN

LH03

SIN

DI0

2+

SIN

BD

02 (s

pect

rom

eter

)

SIN

D01

SIN

BC

02

SIN

BC01

SIN

XB

01

SIN

SB

03

SIN

SB

04

Gun Solenoid

WFG, l = 0.26mBeam Loss

MonitorBLM

Synchrotron Port

CorrectorQuad QFB

Diffraction Radiator

BPM 16

BPMICT

Profile Monitor Collimator0.137 m

TW Cav C-Band1.92 m

27.5 MV/m

281 m

2.93 GeVQuadrupole

QFD (20 T/m)Apert 22 mm

0.15 m

18.2 m

RF Transverse Deflecting Cavities

S20

SY0

3

S30C

B01

S30

CB0

2

S30

CB0

3

S30C

B04

S30C

B05

S30C

B06

S30C

B07

S30

CB0

8

S30C

B09

S30

CB1

0

S30

CB1

1

S30C

B12

S30

CB1

3

S30

CB1

4

BLM

413.6 m

2.1 – 5.8 GeV

SwissFEL Layout (based on FEL-RV84-019-07)

Aramis Undulator Line

Schematic: FEL-GR06-137_4

Leff,quad 0.08 m; |kFODO | 1.88 m

Aramis Line

Beam DumpPavg,max=560 WPpeak,max=46 TW

U15 Undulatorsgap 3.2 – 5.5 mmλu = 15 mm; K= 1.2; LU= 60 m

9.8 m

584 m

gQuad QFM:Leff=0.3 m

Aramis Light2 GW; 66 μJλ =1 (0.8) - 7 Å

5 – 20 fs; 100 Hz

483.7 m; L=2.5 mBeam Stopper

Aramis EnergyCollimator

431 m Dipoles chicaneLeff, dip. =0.5 m; 1º

CorrectorQuadrupole QFB

CorrectorSextupoleHFA

Skew Quadrupoles

BPM8

Alignment Quadrupole QFUProfile monitor(Wire scanner)

608 m

ØV

acuu

m=8

mm

557.7 m

BLM

Tau Monitor

477 m 501 m

Dipole AFBC3 (1º)

ICT

ICT

- Undulator length = 4m, inter-undulator-section = 0.75 m (was 0.9 m)

- Up to 20 undulators U15 can be installed in Aramis beamline

- Normal SASE operation with 12 undulators U15 (to be shown in 2016)Courtesy of Romain Ganter


Outline

• Overview



• Summary


Basic design ideas of SwissFEL undulators

• High stiffness of a rigid frame to achieve hard X-rays down to 1 Å (up to 12.4 keV)

• Cost reduction and optimised design to allow industrial series production

• Modular undulator concept with closed O-shaped structures (closed frames)

• Use of cast and extruded materials is best for low-cost series production

• Precise gap drive system with high stability and drive system on board

• Remote controlled alignment


Basic design idea and concept of SwissFEL undulators

2008: First design idea forU15 and UE40 undulators

2009: Design concept for U152010: Basic Design concept

for U15 is readyDevelopment and Fabrication of Undulator U15 for SwissFEL, Urs Ellenberger MEDSI, Shanghai 2012, October 18 Slide 9

Design of O-shaped frame of mineral cast

Base and side-frames made of cast mineral (Epucret):- Good inner damping characeristics- Non-magnetic- Cost-efficient in series production (vs. granite, cast iron)- Versatile for a defined tubing in a base plate (U15, UE40)

Development and Fabrication of Undulator U15 for SwissFEL, Urs Ellenberger Slide 10MEDSI, Shanghai 2012, October 18

Base frame contains tubes for cabling (depends on undulator).

Wedges are mounted in pairs on rails (Hydrel).

Gap-drive system use servo motors and Beckhoff controls:- One drive system per wedge pair- All four drives have to be synchronized- Outer I-beam is made from extruded aluminum (Alcan),

slides vertically and prevents side motions of wedges.

Aramis Undulator Hybrid – In vacuum

Undulator length 3990 mm

period 15 mm

Number of undulators 12

Number of period segments 266

Nominal K value 1.8 – 1.0

Nominal gap range (20 mm for open gap) 3.2 – 5.5 mm

Pole magnetic field Bz on axis 1.27 – 0.7 T

Cast mineral frame

2.2

m

1.36 m

Gap drive wedge system

Vacuum chamber

4 m

Courtesy of insertion device groupDevelopment and Fabrication of Undulator U15 for SwissFEL, Urs Ellenberger MEDSI, Shanghai 2012, October 18

Specification of undulator U15 of Aramis beamline

Slide 11

Cam-shaft mover (5 axes) remote controlled

Outline

• Overview


• Key components of design- Gap drive system (precision, accuracy)- Outer I-beams (flatness)- Block keepers of inner I-beams to hold the magnets- Automated system for magnet adjustments (ex-vacuum, in-vacuum)- First test results with a micro-undulator

• Summary


Gap variation versus Heidenhain encoder settings


Setup with laser interferometer (0.1 μm accurate) for gap distance measurements

Accuracy of encoder reading is +/- 1 μm (correspondsto +/- 0.1 μm) for gap settings from 3.5 to 6.0 mm.

Gap-drive system use satellite roller screws from Rollvis (CH) to adjust wedges:- A full stroke (360°) corresponds to 1 mm- Verical movement is further reduced by 1:10 through proper wedge dimensions (gearless)

- Minimized backslash (0.3 μm)

Repeatability of a gap settings is +/- 0.5 μm or less depending on the amount of gap change (hysteresis).

Flatness of and parallelism between outer i-beams


Measure of traces on precise machined surface (< 10 μm @ 4m) of I-beams (top and bottom part of frame) with an indicating caliper (1.0 μm accurate)

Differences of corresponding traces (bottom, left) of top and bottom I-beams (first line) do vary in a band of 35 μm (bottom, right) after normalization.

After assembly of top frame (before glueing) Measuring of parallelism between upper and lower I-beam on2 traces (3mm apart):- With laser tracker (10 μm) and with inclinometer (1.0 μm) for comparison.

- Both traces vary in a range of 50 μm.

Simulation of gap dependent magnetic field-distortions due to columns

• Columns connect outer I-beams with inner I-beams in the vacuum vessel

• Number of columns are reduced to save costs (64 to 32, to 20 columns)

• Rearrangement of columns in a shifted way leads to roughly constant gap following a wave

• Simulations show a gap variation which is constant within 1 μm (constant B-field)

• B-field distorsions is expected to be less severe if gap varies with a cosh(z) than with exp(z)

• Less costs for columns and welding, less risk and less assembly workDevelopment and Fabrication of Undulator U15 for SwissFEL, Urs Ellenberger MEDSI, Shanghai 2012, October 18 Slide 15

Magnet, poles and block-keeper units


- Block-keeper made from extruded aluminum for22 periods of magnets mounted on inner I-beam(reduced manufacturing besides wire-cutting EDM)

- Wedge-based height adjustment (flexor or weak-linkmechanism) of max. +/- 20 μm with one screw.

- Automated by robot that drives each screw to correctfor B-field deviation after hall-probe measurements

Microundulator: Setup for B-field measurements (1/3)


- Magnets are NdFeB-Dy, 4.1 mm thick, Cu-Ni coated,remanence Br = 1.25 T, coercitivity Hc > 2‘400 kA/m.

- Pole material is Permendur (CoFeV)- 2x block-keepers are mounted on one I-beam (66 cm

long) to form 44 magnetic periods (period of 15 mm).- Two I-beams are mounted in a rigid microundulator to

serve as a test device for in-air measurements.- B-field variations are measured thorugh a hall-probe

driven by a servo motor on a probe bench. Gap adjustements are calculated and performed by hand.

Planned integrated Hall-probe measurement (2/3)

Development and Fabrication of Undulator U15 for SwissFEL, Urs Ellenberger MEDSI, Shanghai 2012, October 18 Slide 18Hall probe and automated robot with screw-driver for in-air (UE40, Apple) as well as in-vacuum (U-15) measurements.

B-field measurements and calculation of e-trajectories (3/3)


Example of local gap adjustm. (slope = 3.4 gauss/μm) Courtesy of insertion device group

-Measure magnetic field B along the microundulator (y) with the hall probe bench.

- Measure the field integrals of B with the moving wire along the microundulator (y) in x- and z-direction

- Calculate trajectories and phase in (x,y) and (y,z). In (x,y)-plane trajectory of electrons is within 2 μm.

- B-Field profile measurements with the hall probe bench are reproduced by RADIA simulations.

- Results are a corresponding K-value and gap size.

Present status of undulator U15 and outlook

- Prototype has been assembled at MDC (Max Daetwyler Company in Switzerland)- Tests and measurements are within specifications- All four wedge drives have been tested (w/o magnetic forces)- They will be tested again this month by means of pneumatic forces (equal to 3 tons)- Prototype, inner I-beams with keeper blocks, NdFeB(Dy)-magnets, vacuum chamber and columns will be assembled and tested in the insertion device lab on site (PSI)

- Fully functional prototype is expected to be built in the 250 MeV injector in spring 2013


Outline

• Overview



• Summary


Summary

• Design of the undulator U15 is generic (same frame and same gap-drive forother undulators), cost-efficient and optimised for series production.

• Same 5-axis CAM shaft movers, same street transport design (with air cushions)and same supply of material is used for other undulators

• O-shaped frame of mineral cast transfers high stiffness to the inner I-beamand to the magnets where it is required.

• The fully functional prototype (with magnets) will be assembled and testedin the laboratory and will be inserted in the 250 MeV injector in spring 2013.

• Microundulator is used as a test bench for the block-keeper module for theNdFeB-Dy magnets

• Integrated and automated hall-probe measurement has been designed forin-air (ex-vacuum) and in-vacuum systems as well. It will be built and tested.

• This will allow automated adjustments of the magnetic gaps and in case of in-vacuum systems without removing the vacuum chamber (better accuracy).


Development and Fabrication of Undulator U15 for SwissFEL, Urs Ellenberger MEDSI, Shanghai 2012, October 18

On behalf of mechanical engineering departement and of group of insertion devices.

Thank you for your attention.

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Documents

Paul Scherrer Institut - Lawrence Berkeley National Laboratory · 2017-03-30 · Gap-drive system use satellite roller screws from Rollvis (CH) to adjust wedges: - A full stroke (360°)