Neutral atom nuclear EDM Neutral atom nuclear EDM ExperimentsExperiments

Investigating Radium

Lorenz WillmannKVI, Groningen

ECT* Trento, June 21-25, 2004

Outline

• Nuclear edm searches in neutral atoms (199Hg)• Are there other systems

Schiff Moment in Hg, Xe, Rn, Ra, Pu, TlFDzuba, et al., PRA 66, 012111 (2002).

• Enhancements favours Ra:Nuclear StructureAtomic Structure

• Can we exploit natures offer?Road to edm with Radium

Violation of T-Symmetry

H= -(d E+µ B) I/Id - electric dipole momentµ - magnetic dipole momentI - Spin

Limit for nuclear EDM Hgd< 2.1 x 10–28 e cm

M. V. Romalis et al. Phys.Rev.Lett. 86, 2505 (2001)

Radium: Excellent candidateV. A. Dzuba et al. Phys. Rev.A61 062509(2000)

EDMs violate- Parity- Time Reversal

EDM SearchesEDM Searches

• point particles e,,• nucleons n• atoms Tl, Cs, Hg, Ra• Molecules PbO, YbF, TlF

Any object will do need guidance by theory

units 10-27 e cm

exp SM new physics

e (Tl) < 3 10-11 1 < 1.05 109 10-8 200 < 3.1 1011 10-7 1700 n < 63 10-4 60 Tl (odd p) < 105 Hg (odd n) < 0.21 various

What is the source for an EDM?

EDM Now and in the FutureEDM Now and in the Future

1.610-27•

Start TRIP

•199Hg

Radium potential

de (SM) < 10-37

Fortson GroupSeattle, Washington

d < 2.1 10-28 e cm

199Hg Experiment, M. Romalis

From M. Romalis

Fortson GroupSeattle, Washington

Measure EDMMeasure EDM

Prepare Ensemblein Spin State J

Apply Electric Field E

Determination of Ensemble Spin Average

d = Je h

2 m cElectric Dipole Moment:

Precession Frequency:

= d x E

d = 10-25 e cmE = 100 kV/cm = 1.5 *10-5 rad/s

SensitivitySensitivity

P Polarization Efficiency N Number of particles per secondT Measurements Time Spin Coherence Time

Paramenters

1

P N T/)1/2S =

TRITRIPP Radium Permanent Radium Permanent EElectric lectric DDipole ipole MMomentoment

Benefits of RadiumBenefits of Radium • near degeneracy of near degeneracy of 33PP11 and and 33DD22 ~~ 40 000 enhancement40 000 enhancement

• some nuclei strongly deformedsome nuclei strongly deformed spin > 1/2 spin > 1/2 nuclear enhancement nuclear enhancement

50~500 50~500

66

Ra also interesting for weak interaction effectsAnapole moment, weak charge

(Dzuba el al., PRA 6, 062509)

Enhancement of EDMEnhancement of EDM• Heavy Atoms

~ Z2 (RN/RA)

• Induced Dipol Moment Polarizability in nucleus as well as atomic shell

• Example: Tl ~ -585, Fr ~ 1150, Ra ~ 40.000

DA = + c.c. < nl | -de

(-1) E | n’(l+1) > < n’ (l+1) | -er | nl > Enl – En’(l+1)n’

Experimental AspectsExperimental Aspects• CellsCells

high densitymotional fields average to zero long coherence times

• BeamsBeams ultra high vacuum leakage current suppression higher electric fields coherence time limited by length of beam

• TrapsTraps ??no motional electric field, higher densitylong storage time long observation timesultra high vacuum high electric fields possiblesmall sample region homogeneity

• New SystemsNew SystemsNew production facilities for short lived isotopes

IonCatcher

RFQCooler

AtomTrap

Particle Physics Production

TargetMagneticSeparator

MeV meVkeV eV neVAGORcyclotron

TRIP - Trapped Radioactive Isotopes:-laboratories for fundamental Physics

Beyond the Standard Model

TeV PhysicsEDM/-decay

http://www.kvi.nl/~trimp/web/html/trimp.html

Cold Radionuclides WorkCold Radionuclides Work

• Ion traps have been successful Physics Program: mass measurementsnuclear spectroscopycorrelations in -decay

• Now to neutral atomsShort lived isotopes become available for ‘atomic physics’ experiments.

Na, Ne, Rb, Fr, Cs-isotopes, Ra, …

• Worldwide efforts like in Argonne National Lab, GANIL, GSI, Jyvaskylae, KEK, KVI, Stony Brook, TRIUMF …

Target

Gas filled Separator

QDQD

QD QD

208 Pbbeam

T1

TrapExperiments

DD DD

Isotope production @ TRIP KVI

• Separator commissioned with Na production • Ra at TRIP Facility in couple of month

AGOR CyclotronAGOR Cyclotron

Adaptating to New ChallengesAdaptating to New Challenges

• Heavy Ion BeamsHeavy Ion Beams e.g. e.g. 208208PbPb new sourcesnew sources

new injection channelnew injection channelvacuum improvementvacuum improvement

• High Power High Power (TRI(TRIP would appreciate 1 kW)P would appreciate 1 kW)

improved extractionimproved extractionbeam stopsbeam stopsbeam monitoringbeam monitoringradiation safetyradiation safety

Expect 10Expect 1077 213213Ra/kW beamRa/kW beam

AGOR

TRITRIPP

x-ra

y co

unts

[ar

b.]

x-ray energy [channels]

raw data raw data

fitted x-ray spectrafitted x-ray spectra

extracted Fr x-raysextracted Fr x-rays

A. Rogachevsky, H. Wilschut, S. Kopecky,V. Kravchuk, K. Jungmann + AGOR team

FirstFirst TRITRIPP TestsTests1515N N ++ 205205Tl Tl 213213RaRa + 7n + 7n

213213FrFr

C Tl C

NN

RaRa

Fr x-raysFr x-rays

Production Test Production Test 213213RaRa

Expected Production Rates~ 107/s with 1kW primary beam

Radium SpectroscopyRadium Spectroscopy

What do we know?

Radium Spectroscopy DataRadium Spectroscopy DataRadium Discharge analyzed with grating spectrometer

Ebbe Rasmussen, Z. Phys, 87, 607 , 1934; Z. Phys, 86, 24, 1933.

Resolution ~ 0.05 A, 99 lines, absolute accuracy

[A]

Corrections in deduces energy levels

1S0-1P1 1S0-3P1

H.N. Russel, Phys. Rev. 46, 989 (1934)

[A]

Similar to Barium identification as alkaline earth element

482.7 nm

714 nm

7s2 1S0

7s 7p 1P1

7s 7p 3P

7s 6d 1D2

7s 6d 3D1

23

2

1

0

1438 nm1488 nm

2.8 m

Transitions in RadiumTransitions in Radium

Collinear laser spectroscopy 1S0 – 1P1 transitionS.A. Ahmad, W. Klempt, R. Neugart, E.W. Otten, P.-G. Reinhard, G. Ulm K. Wendt and ISOLDE collaboration,Nuclear Physics A483, 244 (1988)

• Spectroscopy of P and D states• Lifetime measurement• Energy level spacing• Hyperfine structure

To do list:

According to NIST Database

Laser Cooling ChartLaser Cooling Chart

Efficient production of cold atoms: Magneto Optical Trap

Other Possibilities: Buffer Gas loading into magnetic trapJ. Doyle, Harvard; A. Richter, Konstanz

KVIRIMSTrace analysis

Next Species

Ba

Ra

Cooling and TrappingCooling and TrappingType Energies Scale

Slowing 1000 m/sZeeman, white light, chirped laser, bichromatic force 100 meV

MOT 100 m/s inhomogeneous B-Field

Optical Molasses 10 m/s, 1 K no B-Field

FORT > 1 mK no B-Field

Magnetic Trap 0.7 K/T/B inhomogeneous B-Field

Cryogenic Buffer 0.7 K/T/B inhomogeneous B-FieldGas Loading

Trap losses: background gas ~1 s @ 10-9 mbaroptical traps not closed cycling scheme

Preliminary Transition Rates as calculated by K. Pachucky (also by V. Dzuba et al.)

Trappist’s ViewTrappist’s View

3*104 s-1

2.2*108 s-1

7s2 1S0

7s 7p 1P1

7s 7p 3P

7s 6d 1D2

7s 6d 3D1

23

2

1

0

1*105 s-1

3*105

1.6*106 s-1

4*103 s-1

CoolingTransition

Repumping necessary

1.4*10-1 s-1

Weaker line, second stage cooling

Repumping

Preliminary Transition Rates as calculated by K. Pachucky (also by V. Dzuba et al.)

Trappist’s ViewTrappist’s View

3*104 s-1

2.2*108 s-1

7s2 1S0

7s 7p 1P1

7s 7p 3P

7s 6d 1D2

7s 6d 3D1

23

2

1

0

1*105 s-1

3*105

1.6*106 s-1

4*103 s-1

Trappist’s ViewTrappist’s View

7s 6d 3D1

23

2.2*108 s-1

7s2 1S0

7s 7p 1P1

7s 7p 3P

7s 6d 1D22

1

0

1.6*106 s-1

Consequences for Laser Cooling with 1S0-3P1

Smaller Enhancement of EDMLonger Lifetime of 3D2 in E-Field

Energy levels calculation3D-States are lower

J. Biron & K. Pachucky (priv. Comm.)

7s 6d 3D1

23

RadiumRadium Spectroscopy Spectroscopy

• Laser Cooling• Metastable Beam

BariumBarium

Heavy Alkaline Earth Element: BariumHeavy Alkaline Earth Element: Barium

– 8.4nsecIs=14mW/cm2

1 2

3

• Life time measurement• Hyperfine structure• Laser cooling of barium• Develop trapping strategy

791.3 nm

6s2 1S0

6s 6p 1P1

6s 5d 1D2

6s 6p 3P210

1130 nm

1499 nm

6s 5d 3D

3 m1108 nm

– 1.4 µsecIs=30µW/cm2

553.7 nm

Ideal testing ground:

No report yet on laser cooling and trapping!No report yet on laser cooling and trapping!

Verdi pumpat 532 nm

Collimator

Ba Oven500C

PD

M1

BS

Dye Laser

PowerStabilization

PMT

AOM

Optical fiber from 791.3 nm diode laser

553.7 nm

Coherent 699Single mode dye laser

B

/2

First StepsFirst Steps

138 B

a

137 B

a F

=5 /

213

7 Ba

F=

5 /2

138 B

a

135 B

a13

6 Ba

in Polarization plane

Polarization plane

Fluorescence at 553.7 nm from different Barium isotopesFluorescence at 553.7 nm from different Barium isotopesC

oun

ts [

kH

z]

PMT

PMT

Cou

nts

[k

Hz]

Frequency [MHz]

Frequency [MHz]

Lifetime Measurement: Hanle effectLifetime Measurement: Hanle effect

Life time of 1P1 state

Laser || B field

eff = h/(2 gJ B1/2)

eff = 8 nsec 0.5sec

138Ba 136Ba

138Ba 136Ba

Cou

nts

[k

Hz]

Cou

nts

[k

Hz]

Cou

nts

[k

Hz]

Cou

nts

[k

Hz]

Magnetic Field [G]

Magnetic Field [G]

Magnetic Field [G]

Magnetic Field [G]

0 100 200 300 400 5000

20

40

60

Grou

nd St

ate D

eplet

ion [%

]

Power [W]

553.7 nm

791.3 nm

6s2 1S0

6s 6p 1P1

6s 6p 3P1

6s 5d 3D

3 m

1.4 µsec

8.4 nsec

40%

60%

Creation of intense beam of meta-stable D-state atoms

321

Intercombination line Intercombination line 11SS00––33PP11

-0.010 -0.005 0.000 0.005-2

-1

0

1

2

Iodi

ne S

igna

l

k + 12636.6632 cm-1 [cm-1]

FM Saturated absorption spectroscopy of IFM Saturated absorption spectroscopy of I22

DiodeLaser791.3 nm

I2 Oven

(560ºC)

M1

M3BS

BSPD

Lock-InAmp

FeedbackControl

VCO

/4 AOM

To Beat note

Lock point

Reference Line P(52)(0-15) transition

f=f0+f1 Sin(wt)

w=90.5kHz

599 MHz away from 1S0–3P1 in 138Ba

(almost one line/5GHz from 500-900nm)

390 400 410 420 430 500 510 520 530 540

0.7

0.8

0.9

1.0

1.1 138Ba136Ba

Dep

leti

on

[%

]

Offset Frequency to I2 reference Line [MHz]

1S0–3P1 transition in an External Magnetic field

= gJ µ mJ B

IS = 138Ba–136Ba= 108.5 (3) MHz

2.3 MHz (FWHM)

• Decay rate• Branching into 3D States

Competitors

RadiumRadium

• Promising candidate for experimental EDM searches

• Production of 213Ra at KVI this year at new TRIP Facility

• Spectroscopy is indispensableLifetimes and Hyperfine Structure

• Development toward trapping with Barium• EDM and Parity violating effects are strong

Next year more about it