Are we ready yet? Where we are. What’s missing. Opportunities for new colleagues/collaborators How long will it take? 29 April 2015 BLV2015 meeting UMASS,

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Are we ready yet?• Where we are. What’s missing.

• Opportunities for new colleagues/collaborators

• How long will it take?

29 April 2015BLV2015 meetingUMASS, Amherst

Storage Ring proton EDM experimentYannis K. Semertzidis, CAPP/IBS and KAIST

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pEDM in all electric ring at BNL Jülich, focus on a smaller radius machine

CW and CCW stored beams

EDMs: Storage ring projects

Yannis Semertzidis, CAPP/IBS, KAIST


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The proton EDM in the AGS tunnel at BNL

Circumference: 800mMax E-field: 4.5MV/m

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Why a large radius ring (sr pEDM)?

1. Electric field needed is moderate (<5MV/m). New techniques with TiN coated Aluminum is a cost savings opportunity.

2. Long horizontal Spin Coherence Time (SCT) w/out sextupoles. (We will be using trims to tune out the sextupoles.)

3. Large ring, requires an existing tunnel


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What has been accomplished?Polarimeter systematic errors (with beams at

KVI, and stored beams at COSY/Germany).Precision beam/spin dynamics tracking.Stable lattice, IBS lifetime: ~104s (Lebedev, FNAL)

Spin coherence time 103 s; role of sextupoles understood (using stored beams at COSY).

Feasibility of required electric field strength <5 MV/m, 3cm plate separation (JLab, FNAL)

Analytic estimation of electric fringe fields and precision beam/spin dynamics tracking. Stable!

(Paper already published or in progress.)

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JLab E-field breakthrough

Large grain Nb, no detectable dark current up to 18 MV/m and 3cm plate gap.

TiN coated Al plates reach high E-field strength

• JLab to test large surface plates


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Single crystal niobium

Field Emission from Niobium

Conventional High Voltage processing: solid data pointsAfter Krypton Processing: open data points

Work of M. BastaniNejadPhys. Rev. ST Accel. Beams, 15,

083502 (2012)

Field strength > 18 MV/m

Buffer chemical polish: less time consuming than diamond paste polishing

JLab results with TiN-coated AluminumNo measureable field emission at 225 kV for gaps > 40 mm, happy at high gradient

Bare Al

TiN-coated Al

the hard coating covers defects

Work of Md. A. Mamun and E. Forman15 MV/m 20 MV/m

Matt Poelker, JLab

At BNL we need <5MV/m for 30mm plate separation

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John Benante, Bill Morse in AGS tunnel, plenty of room for an EDM ring.


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Residual Magnetic Field ( in Gauss) with Hall ProbeLocation E20 upstream 180° 90°1 0.14 0.182 0.20 0.193 0.23 0.174 0.52 0.44

Location F12 upstream 180° 90°5 0.07 0.076 0.06 0.077 0.26 0.218 0.88 0.80

Location L5 upstream 180° 90°9 0.03 0.0610 0.05 0.0611 0.26 0.2612 0.25 0.28

The relative low fields justifies to use AGS tunnel.

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1

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(Measured by John Benante)

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One of the field measurements showing also the oscilloscope data. A small constant was added to these

data to compensate for an instrumental zero-offset.

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The proton EDM ring (alternate gradient)Total circumference: 500 m case

Straight sections are instrumentedwith quads, BPMs, polarimeters,injection points, etc, as needed.

Requirements: Weak vertical focusing (B-fieldsensitivity)Below transition (reduce IBS)

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Booster

Booster-to-AGS BtA Proposed EDM Ring

Beam Injection points

AGS

Q12 of BtA

2nd Inj. Line

1st Inj. LineYannis Semertzidis, CAPP/IBS,

KAIST

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Parallel Beam Displacement in the vertical plane

Dipole

Dipole

quads

quads

Beam

~1m

Vertical Injection Scheme: William Morse-BNL November 18 2014

1m Ferrite kicker magnet100mrad

1m Ferrite kicker magnet100 mrad


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These intensity scan was done in 2009 with Booster input 3*1011. Not much horizontal scan was done since then. The vertical scale is normalized 95% emittance.

The corresponding normalized rms emittance at 1011 is 0.7π horizontal, 1.0π vertical for horizontal scraping.

emittance mw006 chopper

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emittance mw006 vert scrape

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Intensity: 15~2e11 protons @1011

V:6.1πH:4.4π

Emittance out of Booster


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Proton Statistical Error (230MeV):

p : 103s Polarization Lifetime (Spin Coherence Time)A : 0.6 Left/right asymmetry observed by the polarimeterP : 0.8 Beam polarizationNc : 1011p/cycle Total number of stored particles per cycleTTot: 107s Total running time per yearf : 1% Useful event rate fraction (efficiency for EDM)ER : 5 MV/m Radial electric field strength

σd = 1.5×10-29 e-cm / year Yannis Semertzidis, CAPP/IBS, KAIST

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Systematic errorsRecent Breakthroughby David Kawall…

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Clock-wise (CW) & Counter-Clock-wise Storage

Equivalent to p-bar p colliders inMagnetic rings

Total current: zero. Any radial magnetic field in the ring sensed by the stored particles will cause their vertical splitting.


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Distortion of the closed orbit due to Nth-harmonic of radial B-field

Y(ϑ)

Time [s]

Clockwise beam

Counter-clockwise beam

The N=0 componentis a first order effect!

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SQUID BPM to sense the vertical beam splitting at 1-10kHz

First designed byD. KawallUMASS/Amherst

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Total noise of (65) commercially available SQUID gradiometers at KRISS

From YongHo Lee’s groupKRISS/South Korea

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Peter Fierlinger, Garching/Munich

Under development bySelcuk Haciomerogluat CAPP. Need <0.1nT/m

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Peter Fierlinger, Garching/Munich

Getting ready to ship to Korea for integration


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Opportunities for new colleagues and/or collaborators

• Electric field strength issues for large surface plates, dark currents.

• Beam-based alignment, E-field plate alignment (pot. syst. error source).

• Beam impedance issues (pot. syst. error source).


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Technically driven pEDM timeline

• Two years systems development (R&D); CDR; ring design, TDR, installation

• CDR by end of 2016

• Proposal to BNL: fall 2016

2014 15 16 17 18 19 20 21 22 23


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Cost estimate list to be completed within one year

• Injection System • Vacuum System • RF • Spin Rotator RF Dipole • Civil Construction • Project management• SQUID BPM System • Normal BPM System • Magnetic Shielding System • Vacuum Chambers • Electric Deflectors with HV

System • Electric Quads with HV

System • Polarimeters with DAQ• Storage Ring DAQ and Slow

Control• Control Room, Cabling, etc.• Cryogenics/vacuum• Trim E-fields (multipoles)• Helmholtz coils• Installation costs• Beam/spin dynamics,

systematic errors simulations• Beam based alignment

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February 2015


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Let’s indulge on sensitivity• Spin coherence time (104 seconds), stochastic

cooling-thermal mixing, …• Higher beam intensity, smaller IBS

• Reliable E-field 15 MV/m with negligible dark current

• >5% efficient polarimeter, run longer

• Potential gain ~1-2 orders of magnitude in statistical sensitivity: 10-30-10-31 e-cm!

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Summary

• Complementary to LHC; probes New Physics >103 TeV. Received P5 endorsement, from HEPAP 2014.

• Technically driven schedule: CDR by 2016, proposal fall 2016.

• Work on the open questions. Opportunities w/ significant impact are available.


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Extra slides


31Yannis Semertzidis, CAPP/IBS, KAIST

32Yannis Semertzidis, CAPP/IBS, KAIST

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Short History of EDM• 1950’s neutron EDM experiment started to search for

parity violation (Ramsey and Purcell).• After P-violation EDMs require both P,T-Violation• 1960’s EDM searches in atomic systems• 1970’s Indirect Storage Ring EDM method from the

CERN muon g-2 exp.• 1980’s Theory studies on systems (molecules) w/

large enhancement factors• 1990’s First exp. attempts w/ molecules. Dedicated

Storage Ring EDM method developed• 2000’s Proposal for sensitive dEDM exp. developed. • 2010’s Proposal for sensitive pEDM exp. developed.


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The proton EDM ring evaluation Val Lebedev (Fermilab)

Beam intensity 1011 protons limited by IBS

, kV

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E-field plate module: Similar to the (26) FNAL Tevatron ES-separators

0.4 m

3 m

Beam position


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E-field plate module: Similar to the (26) FNAL Tevatron ES-separators

0.4 m

3 m

Beam position


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Extraction: lowering the vertical focusing strength

“defining aperture”polarimeter target

RL

RLH

UD

UDV

carries EDM signalincreases slowly with time

carries in-plane (g-2) precession signal

pEDM polarimeter principle (placed in a straight section in the ring): probing the proton spin components as a function of storage time

Micro-Megas detector, GEMs, MRPC or Si.

Brantjes et al., NIMA 2012.

E. Stephenson

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LEFT UP DOWN RIGHT

Azimuthal angles yield two asymmetries:

RL

RLEDM

UD

UDg

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sensitivity to horizontalcomponent is here

Rings select scattering angle

Bars select azimuthal angle

MXS (large βX)

MXL (large βY)

MXG(large D)

Polarized deuterons

Three sextupole magnet families:

p = 0.97 GeV/c

Carbon block target (17 mm thick)

B E A M

EDDA detectors as polarimeter

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E. Stephenson

COSY ring at Juelich

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The EDM signal: early to late change• Comparing the (left-right)/(left+right) counts vs.

time we monitor the vertical component of spin

(L-R)/(L+R) vs. Time [s]

M.C. data

Opposite helicity bunchesresult to opposite sign slopes

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Large polarimeter analyzing power at Pmagic!


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Spin Coherence Time: need ~103 s• Not all particles have same deviation from

magic momentum, or same horizontal and vertical divergence (all second order effects)

• They cause a spread in the g-2 frequencies:

• Present design parameters allow for 103 s.• Much longer SCT with thermal mixing (S.C.)

22 2

a x y

dPd a b c

P


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The SCT is estimated to be adequate. Confirmed with

independent work: S.H., Y.O., S.M.

How about the proton beam. Are we ready there?


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Major characteristics of a successful Electric Dipole Moment Experiment

• Statistical power: – High intensity beams– Long beam lifetime– Long Spin Coherence Time

• An indirect way to cancel B-field effect• A way to cancel geometric phase effects• Control detector systematic errors• Manageable E-field strength, negligible dark current

The storage ring Proton

EDM method has it all!Yannis Semertzidis, CAPP/IBS,

KAIST

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AGS main magnet field cycle

Fie

ld (

kG)

Time (ms)

The AGS field stays at the injection value between cycles. This value is about 10% of the maximum and can’t be detected by the coils. 10% of the peak values should be added as constant pedestals to each of the curves to the left.

Below cable tray

At magnet height

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International srEDM NetworkCommon R&D

• srEDM Coll. pEDM• Proposal to DOE HEP, NP

• SQUID-based BPMs• B-field

shielding/compensation • Precision simulation• Systematic error studies• E-field tests (low: ~5MV/m)• …

• JEDI (COSY/Jülich)• Pre-cursor EDM exp.

• Polarimeter tests• Spin Coherence Time

tests• Precision simulation• Cooling• E-field tests (high fields)• …


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Small radius ring option (JEDI)

1. Electric field needed is large.

2. Long horizontal Spin Coherence Time (SCT) requires sextupoles.

3. Smaller cost, larger sensitivity

4. More R&D needed on E-field, dark currents.


L = 8.6 mHR = 9.6 WArea = 1.05±0.05 m2

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Electrow

eakB

aryogenises

GU

T S

US

Y

J.M.Pendlebury and E.A. Hinds, NIMA 440 (2000) 471e-cm

Gray: NeutronRed: Electron

n current

n target

Sensitivity to Rule on Several New Models

e current

e targetp, d target

If found it could explainBaryogenesis (p, d, n (or 3He))

Much higher physics reachthan LHC; complementary

Statistics limited

1st upgrade

Electron EDM new physics reach: 1-3 TeV

Documents

Are we ready yet? Where we are. What’s missing. Opportunities for new colleagues/collaborators How long will it take? 29 April 2015 BLV2015 meeting UMASS,