A Path Toward StandardizedA Path Toward Standardized Low-Energy Emittance Low-Energy Emittance

MeasurementsMeasurementsDoug MoehsDoug Moehs

January 17, 2007

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OutlineOutlineLARP Mission and Interests LARP Mission and Interests MotivationMotivationEmittance ProblemEmittance ProblemPossible SolutionPossible Solution

Allison scannerAllison scannerSCUBEXSCUBEX

Conceptual OutlineConceptual OutlineConclusionsConclusions

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LARP Mission and InterestsLARP Mission and Interests

Involve US laboratories in LHC upgradesInvolve US laboratories in LHC upgradesLHC upgradeLHC upgrade plan: Utilize H plan: Utilize H-- beams!!! beams!!!

(http://paf.web.cern.ch/paf/Presentations/PAF_report_ABMB_22May2006.pdf)(http://paf.web.cern.ch/paf/Presentations/PAF_report_ABMB_22May2006.pdf)

Priority 1: HPriority 1: H-- source development source development Priority 2: Linac4 and SPL constructionPriority 2: Linac4 and SPL construction

Develop Accelerator InstrumentationDevelop Accelerator InstrumentationWork at the technological frontierWork at the technological frontier Involve young scientists and studentsInvolve young scientists and students

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MotivationMotivation

R. Scrivens, CERN

All of the CERN upgrade plans include a new HAll of the CERN upgrade plans include a new H-- Linac! Linac! A 3 MeV test stand is now under construction at CERNA 3 MeV test stand is now under construction at CERN This is paralleled by Fermilab's HINS efforts This is paralleled by Fermilab's HINS efforts

January 17, 2007January 17, 2007 Doug MoehsDoug Moehs 55

MotivationMotivation Need Quality low-energy Need Quality low-energy

transverse emittance transverse emittance datadata CERN has no available CERN has no available

emittance probes emittance probes (Thomas Meinschad, CERN Post. Doc. working (Thomas Meinschad, CERN Post. Doc. working

on the CERN 3 MeV H- front end)on the CERN 3 MeV H- front end)

Fermilab probes are old Fermilab probes are old and unreliableand unreliable

HINS is relying on old data HINS is relying on old data from a different LEBT from a different LEBT energy to match to the RFQ energy to match to the RFQ

HINS LEBT-RFQ beam matching

B. Mustapha and P. Ostroumov, ANL

HINS R&D Meeting, December 14, 2006

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Basic DefinitionsBasic DefinitionsMartin Stockli

rmsL

L

FF

xdxdxxA

/)()1ln(2

%) a is (F beamGausian aFor

1),(

Emittance Laboratory Transverse

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Emittance ProblemEmittance Problem Tough to compare Low-Tough to compare Low-

energy emittance valuesenergy emittance values Sensitivity to:Sensitivity to:

How they are measuredHow they are measured Probe typeProbe type

Double slitDouble slit Slit harpSlit harp Pepper potPepper pot

Where they are measuredWhere they are measured After sourceAfter source After LEBT or MEBTAfter LEBT or MEBT

Analysis method usedAnalysis method used ThresholdingThresholding Bias subtractionBias subtraction Eyeballing!Eyeballing!

D. Moehs et al., IEEE Trans, Plas. Sci., 33, 1786, 2005

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Emittance Emittance ProblemProblem

Impedes:Impedes: ion source ion source

selectionselection LEBTLEBT

simulationsimulation DesignDesign

Beam Matching Beam Matching

Historical Magnetron Emittances

D. Moehs, PNNIB, Sante Fe, Sept. 2006

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Possible SolutionPossible Solution

Create a Standard Candle Create a Standard Candle Establish a “standard” probe typeEstablish a “standard” probe typeEstablish a “standard” analysis procedureEstablish a “standard” analysis procedure

A good place to startA good place to startFollow SNS work Follow SNS work (contact: Martin Stockli)(contact: Martin Stockli)

Utilize a highly developed Alision scannerUtilize a highly developed Alision scannerAnalysis software called SCUBEX Analysis software called SCUBEX

Further testing of this software is needed! Further testing of this software is needed!

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Allison ScannerAllison Scanner Double slit Double slit Single charge Single charge

collectorcollector XX

stepping motorstepping motor X’ X’

Electrostatic Electrostatic beam deflectionbeam deflection

Moderate data Moderate data collection speedcollection speed Slower than slit-Slower than slit-

harpharp Faster than Faster than

double slitdouble slit

Some form of this scanner is in use at Some form of this scanner is in use at SNS, LBNL, ORNL(SNS)SNS, LBNL, ORNL(SNS)Picture provided by Martin StockliPicture provided by Martin Stockli

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SCUBEEXSCUBEEX Self Consistent, Unbiased Exclusion Ellipse EXclusion analysisSelf Consistent, Unbiased Exclusion Ellipse EXclusion analysis

Excel macro software developed at SNS to Excel macro software developed at SNS to compute normalized, RMS emittancecompute normalized, RMS emittance

Free but not widely usedFree but not widely used Needs additional debugging and testing Needs additional debugging and testing

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Conceptual OutlineConceptual Outline Construct 3 sets of emittance probes including electronicsConstruct 3 sets of emittance probes including electronics

Follow SNS designFollow SNS design Primary users: CERN, Fermilab and SNSPrimary users: CERN, Fermilab and SNS

Test probes in one locationTest probes in one location Write up operating and analysis techniquesWrite up operating and analysis techniques Disseminate probes and informationDisseminate probes and information

End result comparable emittance data from primary usersEnd result comparable emittance data from primary users Cost to LARPCost to LARP

2 sets of emittance probes and electronics2 sets of emittance probes and electronics Testing and disseminationTesting and dissemination Possible Travel: Possible Travel:

Learn about emittance system operation and data analysis programLearn about emittance system operation and data analysis program Installation and data collection at CERNInstallation and data collection at CERN

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The DESY RF source has been adopted at CERN The DESY RF source has been adopted at CERN The same source is of interest for use on a Proton Driver The same source is of interest for use on a Proton Driver

See (Fermilab AAC 2006 summary talk by Hans Weise)See (Fermilab AAC 2006 summary talk by Hans Weise)

Informal collaboration partners: Fermilab, CERN, DESY, SNSInformal collaboration partners: Fermilab, CERN, DESY, SNS Other labs expressing interest in good emittance data: LANL, ISISOther labs expressing interest in good emittance data: LANL, ISIS

LaboratoryLaboratory CurrentCurrent(mA)(mA)

EmittanceEmittancepi-mm-mr pi-mm-mr (nor., rms ) (nor., rms )

Pulse Pulse LengthLength(ms)(ms)

Rep. Rep. RateRate(Hz)(Hz)

LEBTLEBTEnergyEnergy(keV)(keV)

SNS upgradeSNS upgrade 67 / ~98 67 / ~98 0.2 / 0.350.2 / 0.35 1 1 6060 6565

CERN-SPLCERN-SPLPhase A / BPhase A / B

40 / 80 40 / 80 0.250.25 0.4 / 0.70.4 / 0.7 2 / 50 2 / 50 9595

Fermilab-HINSFermilab-HINSInitial / FinalInitial / Final

13 / 4013 / 40 0.240.24 3 / 13 / 1 2.5 / 102.5 / 10 5050

BSNS*BSNS*Beijing, ChinaBeijing, China

40 40 0.20.2 0.20.2 2525 7575

ISIS upgradeISIS upgrade 7070 0.170.17 1.51.5 5050 7070

Proposed New or Improved Machines

CollaborationsCollaborations

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ConclusionsConclusions

The goals of this project are consistent The goals of this project are consistent with the mission and interests of the LARP with the mission and interests of the LARP collaboration.collaboration.

This project provides timely data for CERN This project provides timely data for CERN and several US laboratories including and several US laboratories including Fermilab.Fermilab.