stephen milton [email protected] system update fac review april 2005 undulator system...

Stephen Milton

[email protected] System Update

FAC Review April 2005

Undulator System Update

Facility Advisory Committee Review

April 7th and 8th 2005

Stephen Milton

Argonne National Laboratory

Advanced Photon Source

Stephen Milton



Outline

Quick Overview

Project Management and Administrative Items

Organization

Plan for the next 6 months

FAC Responses

Magnet Measurement Facility

See Robert Ruland’s Talk in breakout session 1 and J. Sevilla’s breakout session 4.

Physics Topics

Magnet Support System Status

Vacuum System

Diagnostics Status

Building Topics

Controls Status

System Integration Test

Stephen Milton



Undulator System Overview

Stephen Milton



Undulator OrganizationUndulator System

System Manager S. Milton

Chief Engineer/Deputy G. Pile

Magnetic Measurement

R. Ruland

System Layout

TBD

SLAC Integration

B. Youngman

Magnets and Supports

M. White

Vacuum and Diagnostics

D. Walters

Controls

J. Stein

Undulator Physics

H.D. Nuhn

Global Schedule and

Integration

R. Boyce

CF Physics

J. Welch

PMCS Support

P. Mast (AIM)F. Clark (ANL)

Controls System

System Manager

B. Dalesio

Stephen Milton



Faces

Geoff PileANL LCLS Chief Engineer

Responsible for overall undulator system integration and will act in the role of my Deputy

Stephen Milton



Faces

Sushil SharmaFixed Supports Engineer

Will be responsible for the engineering and delivery of the undulator system fixed supports

Has already begun coordinating with Jim Welch

Stephen Milton



Faces

Horst FriedsamANL/SLAC Survey and Alignment LiasonWill coordinate with Robert Ruland to ensure all survey and alignment needs of the undulator system are met

Stephen Milton



New Roles

Undulator Integration Engineer (SLAC)

At SLAC Brad Youngman will oversee daily integration issue for the undulator system

Brad will report directly to Geoff Pile and myself

For administrative purposes Brad will also report to Mark, but ANL will have the final say on what Brad should be doing

Stephen Milton



New Roles

ControlsBob Dalesio directs the overall LCLS Controls effort; therefore,

Josh Stein will work directly with Bob to ensure a robost integration of the overall LCLS controls system

For administrative purposes Josh will still report to me, but Bob will have final say in all controls issues

Stephen Milton



6 Month Look Ahead

BPM SystemBuild cold test prototype x-band beam detectorDesign receiver boards

OTRAssemble and Test Prototype

Wire ScannerAssemble and Test Prototype

Support/Mover SystemAssemble and Test Prototype

1st Article UndulatorsMaybe receive 1st articles from assembly vendors

Fixed SupportsFinalize design and begin procurement for testing

Vacuum ChamberFinalize testing of construction methodsStart building prototype

Project ManagementIt never Ends

Stephen Milton



FAC Responses

Cradle (Mover/Support) System Needs Attention

In addition to Emil Trakhtenberg an additional engineer, Jeff Collins, has been assigned to work on the Mover/Support System

All parts for the prototype have arrived and it will be assembled soon

Stephen Milton



FAC Responses

Trade-offs must be considered to decide whether longer girders can improve tolerance to ground motion

An engineer with experience in girder system (Sushil Sharma) has been assigned to fully develop the fixed support strategy and engineering

He is going over all trade-offs and he is responsible to make the decision, pending review, of the support system used

Stephen Milton



FAC Responses

The FAC recommends that, if the gap/period is changed, a new prototype is not necessary

We are not changing the gap or the period

Consider the use of feed-forward from temperature measurement to adjust the undulator horizontal position and control K

Although this has been discussed and the system is certainly capable of responding in such a fashion, we have not pursued it or tested it yet

Temperature readback of the undulator will be available

Stephen Milton



FAC Responses

The decision has been made to NOT hire a general contractor responsible for delivering complete undulators. The consequences of this decision (plans for control of final assembly) should be presented

The magnet design and engineering has been refined with ease and simplicity of construction in mindA statement of work is being written and will include a complete description of the QA process to be followed

A QA person has been assigned to the projectA complete assembly procedure has been written and a video is being made of the assembly processTwo assembly vendors will be chosenAssembly vendors are being prequalifiedThe 1st article from each of the two vendors will be thoroughly measured and tested before we will accept additional undulatorsFrequent vendor visits will be made to the vendors to perform QA/QC checks and complete assembly travellers will be required for each undulator and component

Stephen Milton



Magnet Measurement Facility

SLAC ScopeANL will act in both mentoring and consulting roles as the facility gets constructed and commissioned.

See Robert Ruland’s talk for more detailsUndulator Measurement/Fiducialization/In-Situ Alignment : Breakout session 1 4:00pm

Stephen Milton



Physics Issues

Break Lengths

AC ConductivityWhat we did

What we decided

Radiation CalculationsPreliminary Results

Next Steps

AlignmentBPM Location

Undulator SectionsWire idea

Feedback

Earth’s Field Correction

Initial Basic Commission Steps

Stephen Milton



Characteristic Lengths Length of Undulator Strongback (Segment):

Lseg = 3.4 m

Distance for 113 x 2 Phase Slippage:L0 = (3.668 m) 3.656 m

Distance for 2 Phase Slippage in Field Free Space:Linc = u (1+K2/2) = 0.214 m

Standard Break Lengths Used Use parameter n to characterize different phase length choices

Ln = L0 - Lseg +(n-1)Linc

Use 2 Short Breaks Followed by 1 Long Break in n-Pattern2 – 2 – 4 ([0.482 m – 0.482 m – 0.910 m]) [0.470 m – 0.470 m – 0.898

m]

Fine Tuning of Initial Break Length Suggested by N. Vinokurov based on Simulations by R. Dejus and N. Vinokurov

using Linear Simulation Code, RON

Small length increases for first 3 break lengths[0.045 m – 0.020 m – 0.005 m]

Total Undulator Length (from beginning of strongback 1 – end of strongback 33):

Lund = (131.59 m) 131.52 m

Undulator Break LengthsUndulator Break Lengths(Old Strategy)(Old Strategy) New Strategy New Strategy

Taking from HD Nuhn’s FAC Talk

Stephen Milton



AC Conductivity

induced energy deviation for round chamber

induced energy deviation for flat chamber

Stephen Milton



AC Conductivity

What’s been doneTheory

Bane, Stupakov, HuangSimulation

Fawley, Reiche, EmmaMeasurements

Yu, Walters

What was decidedThe beam sees AlWe use a flattened cross-sectionWe explore a variety of operating points during commissioning

There will be a much more complete description of what has been done supporting our decision during beakout session 1 of the FAC

Stephen Milton



Radiation Calculations

OTR ScreensWe are concerned that the radiation produced by these screens when inserted into the beam could damage the undulatorBingxin Yang produced a set of conditions and geometries that might be encountered and provided these to the SLAC radiation physicisitAlberto Fassò chose the condition that would produce the most radiation and did simulations of it using his program FLUKA

Stephen Milton




The data in the literature seems to suggest that neutrons are most responsible for the degradation in performance of the permanent magnet blocks.

Stephen Milton




Preliminary ResultsEven with a 100 micron thick screen the simulation suggests that we could operate at 14 GeV with 1nC and at 120 Hz for 10 days before experiencing damaging demagetization

Real operationsWe intend to use foils that are only a micron or two thickWe also plan to use the OTR screens only at low repetition rates (~10 Hz) and they will never be left in while we analyze data

HoweverMagnetic fields were not included in the FLUKA simulationsA field map will be given to Fassò along with other improvements in the geometry and operating conditionsThe simulation will be done again with these improvements

Stephen Milton



Undulator Alignment

Question: How do you ensure that both ends of the undulator are on the desired line?

Beam-based alignment will be used to position the quadrupoles

The quadrupoles are “locked” to the end of the undulator with their magnetic centers aligned to the desired magnetic center of the undulatorThe determines one end of the undulator

New ideaUse a wire at the other end of the undulator that has two positions: one out and one in to a fixed stopThe in position would be accurately aligned to the desired magnetic center of the undulator

Stephen Milton



Undulator Alignment

Stephen Milton



Undulator AlignmentBefore any BBA or wire alignment performed

After BBA: Quad, BPM and one end of the undulator aligned

After Wire Alignment: Both ends of undulator aligned

Stephen Milton



Undulator Alignment

Wire IssuesHow do you distinguish easily between the electron beam and the x-rays

The beam will create an easily seen radiation shower downstream orYou could first extract the undulators

Horizontal positioning is less critical than vertical

Would require a wire after each undulatorNew idea

Needs some time to cook

Stephen Milton



BPM Location

Adjacent to the Quadrupole (SM)If we believe the BPM absolutely then it could go on the other end and be used to align the downstream end of the undulator

No need to do this if we use the wire method

Advantages of being adjacent to the quadrupoleThe quad locations are critical and the is no ambiguity with the BPM adjacent

Following BBA and following quad strength massaging one will have the offset (mechanical and electrical) of the BPM

Stephen Milton



Earth Magnetic Field Compensation StrategyEarth Magnetic Field Compensation Strategy

Earth Magnetic Field along Beam Trajectory in Undulator requires compensation. Estimated strength 0.43±0.06 Gauss : (0.18±0.03, -0.38±0.07,0.08±0.05) Gauss Based on Measurements by K. Hacker. (see LCLS-TN-05-4)

Compensation Strategy: Position the Undulator on Magnetic Measurement Bench in same

direction as in Undulator Tunnel

Compensate Earth Field Component in Undulator in Shimming Process

Scheduling Issues Taken from HD Nuhn’s FAC Presentation

Stephen Milton



Earth Magnetic Field CompensationEarth Magnetic Field CompensationAdjustable Shim ConceptAdjustable Shim Concept

Risk arises from the lack of precise knowledge of the earth field in the tunnel at the time of undulator segment tuning.

Considering mitigation strategy based on use of a small number of precisely adjustable shims along each undulator.

One extra shim per segment will reduce phase error by factor 4.

Shims will be installed before undulator tuning, but adjusted before undulator installation when field error has been determined.

Will not affect definition of magnetic center of undulator (Standard Undulator Axis, SUSA, [see PRD 1.4-001 4.7])

Quad Quad QuadBPMBPMUndulator Undulator

Shim Position Trajectory w/ Shim

Trajectory w/o Shim

Also Taken from HD Nuhn’s FAC Presentation

Stephen Milton



Magnet and Support System Status

Undulator MagnetsLong Lead Procurements

Strong team Lead by M. WhiteTitanium Strongback

Cost increase (Commodities Price)

Magnet PolesCost Decrease (Simplification)

Magnet Blocks

Magnet Assembly

SupportsSupport Mover System

Prototype being assembledMeasurement equipment orderedExpect late May early June Testing

CAM Mover system testSliding stage measurements

Fixed Supports

Stephen Milton



Und. Magnet: LLP, Ti Strongback

StatusTwo Vendors Chosen

Cost higher than expected due to very rapid increase in cost of metal commodities over the last couple of years

Stephen Milton



Und. Magnet: LLP, Magnet Poles

StatusOne Vendor Chosen

Based on cost

This vendor also had experience

Cost came is less than what we originally estimated

Due to simplification of the pole designNo ears

Stephen Milton



Und. Magnet: LLP, Magnet Blocks

StatusRFP Delayed

Spent additional time refining the sorting plan in the statement of work.

The successful vendor will be required to sort the magnet blocks prior to shipment to the assembly vendor

Do not expect the delay to impact the assembly schedule

Stephen Milton



Und. Magnet: Assembly

Plan to go with external assembly vendorsA lot of thought has gone into simplifying the assembly to the point that assembly can be done easily with simple training

How we will do itA statement of work is being written and will include a complete description of the QA process to be followed

A QA person has been assigned to the projectA complete assembly procedure is being written and a video is being made of the assembly processAssembly vendors are being prequalifiedTwo assembly vendors will be chosenThe 1st article from each of the two vendors will be thoroughly measured and tested before we will accept additional undulatorsFrequent vendor visits will be made to perform QA/QC checksComplete assembly travellers will be required for each undulator and component

Stephen Milton



Und. Magnet: Support/Mover SystemPrototype parts in and assembly beginning

Testing expected in May/JuneCAM, Sliding Mechanism, etc. E. Trahktenberg and J. Collins

Stephen Milton



Und. Magnet: Support/Mover System

Detail of Support/Mover System

Stephen Milton



Und. Magnet: Support/Mover System

CAM Mover systemOther system reconsidered

CAM mover still found to be the method of choice

Modifications madeTotal CAM offset reduced to 1.5 mm

Better gearbox

Better bearings

Stephen Milton



Und. Magnet: Fixed Supports

Recent ChangeANL takes over scope of the fixed support system

Experienced engineer assigned to the fixed supportSushil Sharma

In consultation with Jim Welch

Options being reconsideredPast thinking has been to use granite supporting 3 undulators

Other ideas are also being explored

Stephen Milton



Vacuum System

ChangesBeam Sees Aluminum

Al on SSStudy of relative permeability

“Flat” cross-section Construction

Stephen Milton



Vacuum System

Build chamber out of SS coated with AlWhat about the relative permeability?

Curves on the right show the effect of both linear and nonlinear permeability on the undulator field

= 1.115 mm x 5 mm chamber cross-section

Expect SS relative permeabilities of less than 1.01Looks OK but we will be doing more direct measurements to prove this is OK

Waiting for accurate, calibrated permeability meter

0.000 0.002 0.004 0.006 0.008 0.010 0.012 0.014-4.0x10-3

-3.0x10-3

-2.0x10-3

-1.0x10-3

0.0

1.0x10-3

2.0x10-3

3.0x10-3

4.0x10-3

Perturbation from 15mm (H) x 5mm aperture chamber.Constant and nonlinear permeability.

B

[T]

Z [m]

=1.1 Constant =1.1 Nonlinear

0.000 0.002 0.004 0.006 0.008 0.010 0.012 0.014

-4.0x10-4

-2.0x10-4

0.0

2.0x10-4

4.0x10-4

Perturbation from 15mm (H) x 5mm aperture chamber.Constant and nonlinear permeability.

B

[T]

Z [m]

=1.1 Constant =1.1 Nonlinear

Stephen Milton



Chamber Design

Start with SS FlatCoat with AlBend to Desired U shapeWeld to Vacuum Strongback

Stephen Milton



Vacuum Status

Issues to addressSS permeability test

All samples in hand and parts in shops

~1 Month samples ready for measurement

Check of welding, bending, and annealing effects

Survey Market forCoating needs

Polishing needs

Fabrication

Stephen Milton



Diagnostics Status

BPMsLocationPlans

OTR ScreensUseCapabilities

Based on APS Bunch Compressor DesignResolution

Prototype Timeline

Wire ScannersUse

Rethinking need and use

Undulator End Alignment Wire

Intraundulator Xray DetectorsPrototype plans

Waiting for in-vacuum motion tests

Vendor claims they will worksMust pass APS tests first

OtherCharge MonitorsCerenkov Monitors“End-Of-Undulator” Diagnostics

Stephen Milton



Diagnostics Status: BPM

LocationAt the Quad

PlansUse X-Band RF BPM

Internal Dimensions SLAC responsibilityExternal ANL Responsibility

Processing ElectronicsIn-tunnel RF front end mixerGeneric RF front end

Capable for both cavity and stripline

A/D ConverterTeam determined

Stephen Milton



Diagnostics Status: BPM

Prototype PlansBuild 4 cavities

Machining done externallyBrazing done at SLAC or externally

To be determined

Mount three on a rigid support and test with beam

Beam tests to occur at FFTB/SPPS

Closed in Mar. 06?Fall back location will be the APS PAR Bypass line

PC Gun beam with bunch compression

TimescaleWill need 1 year

B. Lill

Stephen Milton



Diagnostics: OTR ScreensUse

Beam distribution measurement along the length of the undulator

Can be used for emittance measurement as twiss parameter checks

FeaturesCommercial 2 inch lens tube, magnification adjustable with change of lensIntegral tungsten shieldStepper driven remote focusDigital video camera, 30-fps at 1 MP, or 120 fps at VROI (250L), programmable gain.Manual iris control5 to 10 micron resolution

Based on APS Bunch Compressor OTR Success

PrototypeParts on orderTesting to occur in summer 05 BX Yang

Stephen Milton



Diagnostics: Wire ScannerBased on SLAC design. Adapted for tighter space.Features

Mounted on 6-inch flangeOn-axis drive mechanism in airShare space with other diagnostics (OTR and x-ray)Wire card to adapt SLAC designTest setup is being designed

Actual use being re-examinedMight switch to the simpler 2 state end alignment wire (see earlier description)

J. Bailey, BX Yang

Stephen Milton



Diagnostics: OTR and WS testingMeasure wire scanner motion accuracy

Calibrate step size and cross check encoder outputsMeasure motion error in all three directionsStudy motion error with different mounting orientation

Characterize OTR camera moduleCalibrate pixel sizeMeasure optical resolution

Status conceptual design in progressIn-Vacuum motors

Waiting for testsVendor claims goodMust pass APS standards

Stephen Milton



Undulator Hall and Buildings

Equipment HallsCable Length Runs

Temperature ControlTight tolerances

20 ± 0.2 CNeeded for undulators (K value)

To minimize thermal expansion problemsMax (Min) Average power +50W/m (-50W/m)Max power fluctuations 5W/m

For more detailsGo to Welch talk at Breakout session 4 of the FAC

Stephen Milton



Undulator Hall and Buildings

Equipment Halls

Maximum Cable Length < 150’

Additional Hole for future extension if needed

6 Undulators servedper drill hole

Requirements/DesiresKeep heat sources out of the tunnelKeep cable lengths to less than 150’Provide for convenient service and maintenance for all electronics

Stephen Milton



Controls Status

OrganizationB. Dalesio in charge of LCLS controlsJ. Stein of ANL matrixed to Dalesio to ensure controls integration between undulator needs and the overall LCLS controls system

Undulator Equipment Halls A lot of work has been done to plan

Cable routingEquipment halls needsRack locations and needs

Major Undulator SystemsMotion Control

CAMs, Horizontal Motion, Intercepting Diagnostics Video

OTR System with up to 120 Hz frame capture rates

Controls PresentationSee J. Stein talk in breakout session 3 of the FAC for more details about the undulator controls

Stephen Milton



Systems Integration Test

One Undulator Support Mover TestsPlan to assemble all major components and systems to test fit and operationsUse the 1st article undulator and prototype mover support systemUse a chamber mockup if a prototype is not availableFall 05

Multi Undulator System Integration TestsBuild up a complete system with at least 2 undulatorsUse 1st articles or prototypes for everything including fixed supportsTest overall assembly, fit, and systemsWinter 06

System Integrations Test PresentationSee M. Whites talk in breakout session 1 of the FAC for more details

Stephen Milton



End of Presentation

stephen milton [email protected] system update fac review april 2005 undulator system...

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system update fac review

bpm system

undulator system brad

overall lcls controls

dalesio slide

deputy slide

stein undulator physics

milton chief engineerdeputyg