Transcript
Page 1: Undulator Alignment Strategy – April 20, 2006 Heinz-Dieter Nuhn, SLAC / LCLS FAC Nuhn@slac.stanford.edu 1 Undulator Alignment Strategy Heinz-Dieter Nuhn,

1Undulator Alignment Strategy – April 20, 2006 Heinz-Dieter Nuhn, SLAC / LCLSFAC [email protected]@slac.stanford.edu

Undulator Alignment StrategyHeinz-Dieter Nuhn, SLAC / LCLS

April 20, 2006

Undulator Alignment StrategyHeinz-Dieter Nuhn, SLAC / LCLS

April 20, 2006

Alignment Overview Alignment Tolerances Alignment Monitoring Correction Zones

Alignment Overview Alignment Tolerances Alignment Monitoring Correction Zones

Page 2: Undulator Alignment Strategy – April 20, 2006 Heinz-Dieter Nuhn, SLAC / LCLS FAC Nuhn@slac.stanford.edu 1 Undulator Alignment Strategy Heinz-Dieter Nuhn,

2Undulator Alignment Strategy – April 20, 2006 Heinz-Dieter Nuhn, SLAC / LCLSFAC [email protected]@slac.stanford.edu

Undulator Alignment Overview

The focus of the undulator alignment is on Quadrupoles and Beam Position Monitors (BPMs)

Beam Finder Wires (BFW)

Undulator Strongbacks (Segments)

The alignment procedures includeGirder Component Alignment [checked on CMM]

Conventional Tunnel Alignment

Beam Based Alignment (BBA) [Energy Scan followed by BFW]

Continuous Monitoring and Correcting of Component Positions

Auxiliary alignment procedures includeSegment Fiducialization [SUSA wrt. Segment fiducials]

Quadrupole Fiducialization [Magnetic center wrt. Quad fiducials]

BFW Fiducialization [Wire location wrt. BFW fiducials]

The focus of the undulator alignment is on Quadrupoles and Beam Position Monitors (BPMs)

Beam Finder Wires (BFW)

Undulator Strongbacks (Segments)

The alignment procedures includeGirder Component Alignment [checked on CMM]

Conventional Tunnel Alignment

Beam Based Alignment (BBA) [Energy Scan followed by BFW]

Continuous Monitoring and Correcting of Component Positions

Auxiliary alignment procedures includeSegment Fiducialization [SUSA wrt. Segment fiducials]

Quadrupole Fiducialization [Magnetic center wrt. Quad fiducials]

BFW Fiducialization [Wire location wrt. BFW fiducials]

Page 3: Undulator Alignment Strategy – April 20, 2006 Heinz-Dieter Nuhn, SLAC / LCLS FAC Nuhn@slac.stanford.edu 1 Undulator Alignment Strategy Heinz-Dieter Nuhn,

3Undulator Alignment Strategy – April 20, 2006 Heinz-Dieter Nuhn, SLAC / LCLSFAC [email protected]@slac.stanford.edu

Main Alignment Concepts

Pre-alignment (baselining) uses the manual adjustments on top of the support structures.Relative alignment of Girder components is achieved and maintained through common-girder mounting checked by CMMGirder-to-Girder alignment is (remotely) controlled based on cam-shaft technology

During initial alignment [with focus on quadrupole and BFW positions]For quadrupole position control, i.e. beam steering during BBAFor compensation of ground motion effects etc.

Beam-Based-Alignment uses quadrupole magnets in two ways:1) via off-center dipole fields. [Change is done through cam-based girder

motion, which will align all girder components to the beam. Minimum motion range covers area of circle with 700 µm radius ]

2) via dipole trim-windings on Quadrupole Magnets (used for fine adjustments.) [Range equivalent to ±100 µm of Quad motion]

Pre-alignment (baselining) uses the manual adjustments on top of the support structures.Relative alignment of Girder components is achieved and maintained through common-girder mounting checked by CMMGirder-to-Girder alignment is (remotely) controlled based on cam-shaft technology

During initial alignment [with focus on quadrupole and BFW positions]For quadrupole position control, i.e. beam steering during BBAFor compensation of ground motion effects etc.

Beam-Based-Alignment uses quadrupole magnets in two ways:1) via off-center dipole fields. [Change is done through cam-based girder

motion, which will align all girder components to the beam. Minimum motion range covers area of circle with 700 µm radius ]

2) via dipole trim-windings on Quadrupole Magnets (used for fine adjustments.) [Range equivalent to ±100 µm of Quad motion]

Page 4: Undulator Alignment Strategy – April 20, 2006 Heinz-Dieter Nuhn, SLAC / LCLS FAC Nuhn@slac.stanford.edu 1 Undulator Alignment Strategy Heinz-Dieter Nuhn,

4Undulator Alignment Strategy – April 20, 2006 Heinz-Dieter Nuhn, SLAC / LCLSFAC [email protected]@slac.stanford.edu

Girder Components Summary

Main girder components includeBeam Finder Wire (BFW)Undulator strongback arrangement mounted on horizontal slidesVacuum chamber supportBPMQuadrupoleMounts for the Wire Position Monitor (WPM) systemSensors of the Hydrostatic Leveling System (HLS) Diagnostics components

The undulator strongback arrangement (Segment) is mountable on and removable from the girder with the vacuum chamber in place and without compromising the alignment of the vacuum chamberSegments will be taken off the girder for magnetic measurementsSegments will be interchangeable without the need for the CMMThe complete girder assembly will be aligned on the Coordinate Measurement Machine (CMM).

Main girder components includeBeam Finder Wire (BFW)Undulator strongback arrangement mounted on horizontal slidesVacuum chamber supportBPMQuadrupoleMounts for the Wire Position Monitor (WPM) systemSensors of the Hydrostatic Leveling System (HLS) Diagnostics components

The undulator strongback arrangement (Segment) is mountable on and removable from the girder with the vacuum chamber in place and without compromising the alignment of the vacuum chamberSegments will be taken off the girder for magnetic measurementsSegments will be interchangeable without the need for the CMMThe complete girder assembly will be aligned on the Coordinate Measurement Machine (CMM).

Page 5: Undulator Alignment Strategy – April 20, 2006 Heinz-Dieter Nuhn, SLAC / LCLS FAC Nuhn@slac.stanford.edu 1 Undulator Alignment Strategy Heinz-Dieter Nuhn,

5Undulator Alignment Strategy – April 20, 2006 Heinz-Dieter Nuhn, SLAC / LCLSFAC [email protected]@slac.stanford.edu

Beam Finder Wire (BFW)

Vacuum Chamber

Wake Mitigation

Wires

BFW

Beam Direction

A misaligned undulator will not steer the beam. It will just radiate at the wrong wavelength.The BFW allows the misalignment to be detected. (also allows beam size measurements)

A misaligned undulator will not steer the beam. It will just radiate at the wrong wavelength.The BFW allows the misalignment to be detected. (also allows beam size measurements)

Undulator QuadBFW

Page 6: Undulator Alignment Strategy – April 20, 2006 Heinz-Dieter Nuhn, SLAC / LCLS FAC Nuhn@slac.stanford.edu 1 Undulator Alignment Strategy Heinz-Dieter Nuhn,

6Undulator Alignment Strategy – April 20, 2006 Heinz-Dieter Nuhn, SLAC / LCLSFAC [email protected]@slac.stanford.edu

Undulator–to–Quad FiducializationTolerance Budget

Vertical Horizontal [µm] [µm] Quadrupole Fiducials Pulsed Wire Center Definition 10 10 Wire to Wire Finder (WF) Fiducial 20 20 WF Fiducial to Quadrupole Fiducial 10 10 25 25 Quadrupole BBA Offset 20 20 Undulator Fiducials Hall Probe Resolution/Positioning 20 20 Needle Hall Probe Resolution 15 30 Needle Center to Fiducial 20 30 Fixture Fiducial to Undulator Fiducial 20 20 40 50 Undulator Segment Roll-Away Repeatability 10 10 Alignment Quadrupole to Undulator 60 125 Grand Total [Beam-to-Undulator] 80 140

Individual contributions are added in quadratureIndividual contributions are added in quadrature

Page 7: Undulator Alignment Strategy – April 20, 2006 Heinz-Dieter Nuhn, SLAC / LCLS FAC Nuhn@slac.stanford.edu 1 Undulator Alignment Strategy Heinz-Dieter Nuhn,

7Undulator Alignment Strategy – April 20, 2006 Heinz-Dieter Nuhn, SLAC / LCLSFAC [email protected]@slac.stanford.edu

Undulator–to–BFW FiducializationTolerance Budget

Vertical Horizontal [µm] [µm] BFW Fiducials BFW Wire to Reference Stop 20 20 Reference Stop Definition 10 10 Reference Stop Fiducial 20 20 30 30 Undulator Fiducials Hall Probe Resolution/Positioning 20 20 Needle Hall Probe Resolution 15 30 Needle Center to Fiducial 20 30 Fixture Fiducial to Undulator Fiducial 20 20 40 50 X-Wire Positioning Repeatability - 80 Y-Wire Positioning Repeatability 30 - CAM Positioning Repeatability 4 4 Undulator Segment Roll-Away Repeatability 10 10 Alignment BFW to Undulator 55 100 Grand Total [Beam-to-Undulator] 80 140

Individual contributions are added in quadratureIndividual contributions are added in quadrature

Page 8: Undulator Alignment Strategy – April 20, 2006 Heinz-Dieter Nuhn, SLAC / LCLS FAC Nuhn@slac.stanford.edu 1 Undulator Alignment Strategy Heinz-Dieter Nuhn,

8Undulator Alignment Strategy – April 20, 2006 Heinz-Dieter Nuhn, SLAC / LCLSFAC [email protected]@slac.stanford.edu

Alignment Tolerance Summary

Tolerances for Girder Alignment in Tunnel Value Unit

Initial rms uncorrelated x/y quadrupole alignment tolerance wrt straight line 100 µm

Initial rms correlated x/y quadrupole alignment tolerance wrt straight line 300 µm

Longitudinal Girder alignment tolerance ±1 mm

Undulator Segment yaw tolerance (rms) 240 µrad

Undulator Segment pitch tolerance (rms) 80 µrad

Undulator Segment roll tolerance (rms) 1000 µrad

Component Monitoring and Control Tolerance Value Unit

Horizontal / Vertical Quadrupole and BPM Positions (Depending on Zone) ±2 µm

Tolerances for Component Alignment on Girder Value Unit

Horizontal alignment of quadrupole and BPM to Segment (rms) 125 µm

Vertical alignment of quadrupole and BPM to Segment (rms) 60 µm

Horizontal alignment of BFW to Segment (rms) 100 µm

Vertical alignment of BFW to Segment (rms) 55 µm

Page 9: Undulator Alignment Strategy – April 20, 2006 Heinz-Dieter Nuhn, SLAC / LCLS FAC Nuhn@slac.stanford.edu 1 Undulator Alignment Strategy Heinz-Dieter Nuhn,

9Undulator Alignment Strategy – April 20, 2006 Heinz-Dieter Nuhn, SLAC / LCLSFAC [email protected]@slac.stanford.edu

Survey Monuments

wall monuments

(with removable spherical target)

floor monument

(with removable spherical target)

6’

1‘ stay-clear

Extract from ESD 1.4-113 Undulator Tunnel Survey Monument Positions B. Fuss

Page 10: Undulator Alignment Strategy – April 20, 2006 Heinz-Dieter Nuhn, SLAC / LCLS FAC Nuhn@slac.stanford.edu 1 Undulator Alignment Strategy Heinz-Dieter Nuhn,

10Undulator Alignment Strategy – April 20, 2006 Heinz-Dieter Nuhn, SLAC / LCLSFAC [email protected]@slac.stanford.edu

Undulator Hall Network

dh = 50 μm

1600 1650 1700 1750 1800 1850 1900 1950 2000 2050 2100 2150 2200 2250

UH Tunnel StartSTA 1672.09 ft509.653 m

SLOPE SLOPE

UH Tunnel WestSide Thermal BarrierSTA 2237.33 ft681.939 m

Undulator Hall Tunnel

BTH

BeamDump24” Vertical Penetration

(approx. position)

D = 30 μm h = 30 μm / D v =50 μm /D

z = 22 μm x = 47 μm y =46 μm

Inputs:

Results:

Quadruples

Level

Monuments Tracker Positions

Tracker

Page 11: Undulator Alignment Strategy – April 20, 2006 Heinz-Dieter Nuhn, SLAC / LCLS FAC Nuhn@slac.stanford.edu 1 Undulator Alignment Strategy Heinz-Dieter Nuhn,

11Undulator Alignment Strategy – April 20, 2006 Heinz-Dieter Nuhn, SLAC / LCLSFAC [email protected]@slac.stanford.edu

Undulator Alignment Controls

Manual Adjustability:Rough CAM position adjustability relative to fixed support.ranges: x (12 mm); y (25 mm); z (12 mm)Quadrupole, BFW, BPM, Vacuum Chamber, and Segment adjustability to Girder. ranges: x (>1 mm); y (>1 mm); z (>1 mm)

Remote Adjustability:Girder: x, y, pitch, yaw, roll [1.5 mm x and y]

Enables alignment of all beamline components to the beam axis.Roll motion capability is to be used to keep roll constant

Undulator: x [ 80 mm range]Provides control of undulator field on beam axis.Horizontal slide stages move undulator strongback independent of Girder and vacuum chamber.

Manual Adjustability:Rough CAM position adjustability relative to fixed support.ranges: x (12 mm); y (25 mm); z (12 mm)Quadrupole, BFW, BPM, Vacuum Chamber, and Segment adjustability to Girder. ranges: x (>1 mm); y (>1 mm); z (>1 mm)

Remote Adjustability:Girder: x, y, pitch, yaw, roll [1.5 mm x and y]

Enables alignment of all beamline components to the beam axis.Roll motion capability is to be used to keep roll constant

Undulator: x [ 80 mm range]Provides control of undulator field on beam axis.Horizontal slide stages move undulator strongback independent of Girder and vacuum chamber.

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12Undulator Alignment Strategy – April 20, 2006 Heinz-Dieter Nuhn, SLAC / LCLSFAC [email protected]@slac.stanford.edu

Undulator Segment Supports

Fixed Supports

Horizontal SlidesSegment

Cam Movers

ManualAdjustments

Girder

Manual Adjustments

Vacuum Chamber Support

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13Undulator Alignment Strategy – April 20, 2006 Heinz-Dieter Nuhn, SLAC / LCLSFAC [email protected]@slac.stanford.edu

Page 14: Undulator Alignment Strategy – April 20, 2006 Heinz-Dieter Nuhn, SLAC / LCLS FAC Nuhn@slac.stanford.edu 1 Undulator Alignment Strategy Heinz-Dieter Nuhn,

14Undulator Alignment Strategy – April 20, 2006 Heinz-Dieter Nuhn, SLAC / LCLSFAC [email protected]@slac.stanford.edu

Undulator Alignment Monitoring Elements

Hydrostatic Leveling System (HLS)Monitored Degrees of Freedom are: y, pitch, and roll

Wire Position Monitoring System (WPM)Monitored Degrees of Freedom are: x, (y), (pitch), yaw, and roll

Temperature SensorsIn support of HLS/WPM readout corrections, undulator K corrections, and component motion interpretation.

Beam Position Monitors* Monitored quantities are: x and y position of electron beam

Quadrupoles* Monitored quantities are: electron beam x and y offset from quad center

Hydrostatic Leveling System (HLS)Monitored Degrees of Freedom are: y, pitch, and roll

Wire Position Monitoring System (WPM)Monitored Degrees of Freedom are: x, (y), (pitch), yaw, and roll

Temperature SensorsIn support of HLS/WPM readout corrections, undulator K corrections, and component motion interpretation.

Beam Position Monitors* Monitored quantities are: x and y position of electron beam

Quadrupoles* Monitored quantities are: electron beam x and y offset from quad center

*Transverse Locations Tracked by HLS and WPM*Transverse Locations Tracked by HLS and WPM

Page 15: Undulator Alignment Strategy – April 20, 2006 Heinz-Dieter Nuhn, SLAC / LCLS FAC Nuhn@slac.stanford.edu 1 Undulator Alignment Strategy Heinz-Dieter Nuhn,

15Undulator Alignment Strategy – April 20, 2006 Heinz-Dieter Nuhn, SLAC / LCLSFAC [email protected]@slac.stanford.edu

610 mm

240

280

Wire1

Wire2

Position Monitor

Component Position Monitoring Systems(Alignment Diagnostics System – ADS)

UltrasoundProbe

Fiducial

Reference surfaces

• Resolution < 100 nm in X & Y direction• Instrument Drift < 100 nm per day• Moving Range ±1.5 mm in X & Y direction• Accuracy 0.1 % of full Scale • Availability Permanent, no interrupts

Wire Position Monitor system (WPM)

Hydrostatic Leveling System (HLS)

• Precision < 1 m• Instrument Drift ~1-2 m / month• Accuracy < 0.1 % of full Scale

Capacitive Sensor

Ultrasound Sensor• Precision < 0.1 m • Instrument Drift potentially no drift• Accuracy < 0.1 % of full Scale

HLS 1 HLS 2

HLS 4 HLS 3Beam

pitch

rollheight

Ceramic plate

ElectronicSensing Electrode

eAir

eWater DWater

DAir

X and Y, can be measuredRoll, Jaw & Pitch can be calculated.

Pitch

Y Roll

Y, can be measuredRoll & Pitch can be calculated.

Page 16: Undulator Alignment Strategy – April 20, 2006 Heinz-Dieter Nuhn, SLAC / LCLS FAC Nuhn@slac.stanford.edu 1 Undulator Alignment Strategy Heinz-Dieter Nuhn,

16Undulator Alignment Strategy – April 20, 2006 Heinz-Dieter Nuhn, SLAC / LCLSFAC [email protected]@slac.stanford.edu

ADS…Common Sensor Support

Quadrupole X & Y- Position will be measured relative to the references.

Roll, Pitch, Yaw and Torsion of the Girder can be calculated.

84

375

130

200

20

0

50

260

90

265

102

550

60

470

80

720

93

245

25

60

Girder Girder

Girder

Strongback

HLS pots

WPM supports

2" Pipe

115

Quadrupole

Beam

WPM stay clear areaalong entire Undulator

Yellow parts = Interface of WPM & HLS to grider

H2O Level

155

50

55

M10

Wire Position Monitor & Hydro Level System Interface

SLAC / LCLSF. Peters

Version:

Engineering:

Revision:03/23/06

005

G. Gassner

Dimensions in Millimeter

M6M6

Dis

tan

ce t

o flo

or

140

0 m

m

170

245 245

360

562

Page 17: Undulator Alignment Strategy – April 20, 2006 Heinz-Dieter Nuhn, SLAC / LCLS FAC Nuhn@slac.stanford.edu 1 Undulator Alignment Strategy Heinz-Dieter Nuhn,

17Undulator Alignment Strategy – April 20, 2006 Heinz-Dieter Nuhn, SLAC / LCLSFAC [email protected]@slac.stanford.edu

Strategies for Controlling Component Motion

Girder motion will be caused byGround Motion

Temperature Changes

CAM Rotation

Girder motion will be monitored in 2 ways.1. Directly, through the Alignment Diagnostics System

2. Indirectly, through impact on electron beam trajectory (as detected by BPMs)

Girder Positions will be frequently corrected using the CAM movers.

Page 18: Undulator Alignment Strategy – April 20, 2006 Heinz-Dieter Nuhn, SLAC / LCLS FAC Nuhn@slac.stanford.edu 1 Undulator Alignment Strategy Heinz-Dieter Nuhn,

18Undulator Alignment Strategy – April 20, 2006 Heinz-Dieter Nuhn, SLAC / LCLSFAC [email protected]@slac.stanford.edu

Zone 1Zone 1 (non-invasive correction) (non-invasive correction)• 120-Hz traj-feedback (LTU BPM’s)120-Hz traj-feedback (LTU BPM’s)• 0.1-Hz traj-feedback (und. BPM’s)0.1-Hz traj-feedback (und. BPM’s)

Zone 2Zone 2 ( (tt > 1 hr, > 1 hr, PP//PP00 > 90%, non-invasive) > 90%, non-invasive)• Maintain component alignment based on ADSMaintain component alignment based on ADS

Correction Zones

Zone 3Zone 3 ( (tt > 24 hr, > 24 hr, PP//PP00 > 90%, non-invasive) > 90%, non-invasive)• Maintain component alignment based on ADSMaintain component alignment based on ADS• Possible x-ray pointing correctionPossible x-ray pointing correction

Zone 4Zone 4 ( (tt > 1 mo, > 1 mo, PP//PP00 > 75%, machine time) > 75%, machine time)• One iteration of BBA (<1 hr)One iteration of BBA (<1 hr)

Zone 5 (Zone 5 (tt > 6 mo, shut-down) > 6 mo, shut-down)• Reset movers set to zero and manual realignment (1 wk)Reset movers set to zero and manual realignment (1 wk)• Full 3 iterations of BBA (~3 hrs)Full 3 iterations of BBA (~3 hrs)

mo

Page 19: Undulator Alignment Strategy – April 20, 2006 Heinz-Dieter Nuhn, SLAC / LCLS FAC Nuhn@slac.stanford.edu 1 Undulator Alignment Strategy Heinz-Dieter Nuhn,

19Undulator Alignment Strategy – April 20, 2006 Heinz-Dieter Nuhn, SLAC / LCLSFAC [email protected]@slac.stanford.edu

Undulator HallMMF

Alignment Function Diagram

Segment Tuning and Fiducialization

Quadrupole Fiducialization

BFW Fiducialization

Component Alignment on Girder

Environmental Field Measurement

Girder Pre- Alignment

ADS Installation

Girder Alignment using ADS

Loose End-Alignment

Undulator Segment Installation

Electron Beam-Based Alignment

USE OF DIAGNOSTICS COMPONENTS

Supports Alignment

BPMs QuadsBFWs

Once per month: Swap 3 Segments

Continuous Position Correction

Once every 6 month: Re-baselining

Every 2 – 4 weeks: Invasive Correction

Segment Tuning ADS(HLS/WPM)

Page 20: Undulator Alignment Strategy – April 20, 2006 Heinz-Dieter Nuhn, SLAC / LCLS FAC Nuhn@slac.stanford.edu 1 Undulator Alignment Strategy Heinz-Dieter Nuhn,

20Undulator Alignment Strategy – April 20, 2006 Heinz-Dieter Nuhn, SLAC / LCLSFAC [email protected]@slac.stanford.edu

The X-ray-FEL puts very tight tolerances on magnetic field quality, electron beam straightness, and Segment alignment.

These tolerances can be achieved through Beam Based Alignment (BBA) procedures based on BPMs and Quadrupoles (with energy scan) as well as BFWs.

Relative component alignment to required tolerances will be achieved through common girder mounting.

Main tasks of the conventional alignment and motion systems areComponent fiducialization and alignment on girder

Conventional alignment of girders in Undulator Hall as prerequisite for BBA

The Alignment Diagnostic System measures and enables the correction of girder movement due to ground motion, temperature changes, and CAM mover changes.

A strategy is in place for using the monitor systems and controls to establish and maintain a straight trajectory.

The X-ray-FEL puts very tight tolerances on magnetic field quality, electron beam straightness, and Segment alignment.

These tolerances can be achieved through Beam Based Alignment (BBA) procedures based on BPMs and Quadrupoles (with energy scan) as well as BFWs.

Relative component alignment to required tolerances will be achieved through common girder mounting.

Main tasks of the conventional alignment and motion systems areComponent fiducialization and alignment on girder

Conventional alignment of girders in Undulator Hall as prerequisite for BBA

The Alignment Diagnostic System measures and enables the correction of girder movement due to ground motion, temperature changes, and CAM mover changes.

A strategy is in place for using the monitor systems and controls to establish and maintain a straight trajectory.

Conclusions

Page 21: Undulator Alignment Strategy – April 20, 2006 Heinz-Dieter Nuhn, SLAC / LCLS FAC Nuhn@slac.stanford.edu 1 Undulator Alignment Strategy Heinz-Dieter Nuhn,

21Undulator Alignment Strategy – April 20, 2006 Heinz-Dieter Nuhn, SLAC / LCLSFAC [email protected]@slac.stanford.edu

End of Presentation


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