Neutral atom nuclear EDM Experiments

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Neutral atom nuclear EDM Experiments

• Investigating Radium

Lorenz Willmann KVI, Groningen
ECT Trento, June 21-25, 2004
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Outline

• Nuclear edm searches in neutral atoms (199Hg)
• Are there other systems Schiff Moment in
  Hg, Xe, Rn, Ra, Pu, TlF Dzuba, et al., PRA 66,
  012111 (2002).
• Enhancements favours Ra Nuclear
  Structure Atomic Structure
• Can we exploit natures offer? Road to edm with
  Radium

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Violation of T-Symmetry

• H -(d Eµ B) I/I
• d - electric dipole moment
• µ - magnetic dipole moment
• I - Spin
• Limit for nuclear EDM Hg
• dlt 2.1 x 1028 e cm
• M. V. Romalis et al. Phys.Rev.Lett. 86, 2505
  (2001)
• Radium Excellent candidate
• V. A. Dzuba et al. Phys. Rev.A61 062509(2000)

EDMs violate - Parity - Time Reversal
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EDM Searches
Any object will do ? need guidance by theory

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

What is the source for an EDM?
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EDM Now and in the Future
1.6?10-27


199Hg
Radium potential
Start TRI?P
de (SM) lt 10-37
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199Hg Experiment, M. Romalis
Fortson Group Seattle, Washington
d lt 2.1 10-28 e cm
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Fortson Group Seattle, Washington
From M. Romalis
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Measure EDM
Prepare Ensemble in Spin State J
Apply Electric Field E
Determination of Ensemble Spin Average
Precession Frequency
? d x E
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Sensitivity
Paramenters
P Polarization e Efficiency N Number of
particles per second T Measurements Time t
Spin Coherence Time

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TRImP
Radium Permanent Electric Dipole Moment

• Benefits of Radium
• near degeneracy of 3P1 and 3D2
• ? 40 000 enhancement
• some nuclei strongly deformed spin gt 1/2
• ? nuclear enhancement
• 50500

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Ra also interesting for weak interaction
effects Anapole moment, weak charge (Dzuba el
al., PRA 6, 062509)
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Enhancement 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

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Experimental Aspects

• Cells ? high density motional fields average
  to zero long coherence times
• Beams ? ultra high vacuum leakage current
  suppression higher electric fields coherence
  time limited by length of beam
• Traps ? no motional electric field, higher
  density long storage time ? long
  observation times ultra high vacuum ? high
  electric fields possible small sample region ?
  homogeneity
• New Systems
• New production facilities for short lived
  isotopes

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TRI?P - Trapped Radioactive Isotopes?-laboratori
es for fundamental Physics
Ion Catcher
RFQ Cooler
Atom Trap
Production Target
Magnetic Separator
Particle Physics
Beyond the Standard Model TeV Physics EDM/?-decay
AGOR cyclotron
MeV
meV
keV
eV
neV
http//www.kvi.nl/trimp/web/html/trimp.html
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Cold Radionuclides Work

• Ion traps have been successful Physics Program
  mass measurementsnuclear spectroscopycorrelation
  s in ?-decay
• Now to neutral atoms
• Short 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

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Isotope production _at_ TRI?P KVI
QD
QD
DD
DD
Target
QD
QD
Gas filled Separator
T1

208 Pb beam
Trap Experiments

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

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AGOR
AGOR Cyclotron

• Adaptating to New Challenges
• Heavy Ion Beams
• ? e.g. 208Pb
• new sources
• new injection channel
• vacuum improvement
• High Power (TRImP would appreciate 1 kW)
• improved extraction
• beam stops
• beam monitoring
• radiation safety
• Expect 107 213Ra/kW beam

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Production Test 213Ra
TRImP
fitted x-ray spectra
x-ray counts arb.
extracted Fr x-rays
raw data
Expected Production Rates 107/s with 1kW
primary beam
x-ray energy channels
A. Rogachevsky, H. Wilschut, S. Kopecky, V.
Kravchuk, K. Jungmann AGOR team
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Radium Spectroscopy
What do we know?
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Radium Spectroscopy Data
Radium 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
1S0-1P1
1S0-3P1
Corrections in deduces energy levels
H.N. Russel, Phys. Rev. 46, 989 (1934)
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Transitions in Radium
According to NIST Database

Collinear laser spectroscopy 1S0 1P1
transition S.A. Ahmad, W. Klempt, R. Neugart,
E.W. Otten, P.-G. Reinhard, G. Ulm K. Wendt and
ISOLDE collaboration, Nuclear Physics A483, 244
(1988)
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Laser Cooling Chart
Efficient production of cold atoms Magneto
Optical Trap Other Possibilities Buffer Gas
loading into magnetic trap J. Doyle, Harvard A.
Richter, Konstanz
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Cooling and Trapping
Trap losses background gas 1 s _at_ 10-9
mbar optical traps ? not closed cycling scheme
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Trappists View
Preliminary Transition Rates as calculated by K.
Pachucky (also by V. Dzuba et al.)
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Trappists View
Preliminary Transition Rates as calculated by K.
Pachucky (also by V. Dzuba et al.)
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Trappists View
Consequences for Laser Cooling with
1S0-3P1 Smaller Enhancement of EDM Longer
Lifetime of 3D2 in E-Field
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Radium Spectroscopy
Barium

• Laser Cooling
• Metastable Beam

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Heavy Alkaline Earth Element Barium
Ideal testing ground
? 8.4nsec Is14mW/cm2

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

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2
1
No report yet on laser cooling and trapping!
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First Steps
Verdi pump at 532 nm
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Fluorescence at 553.7 nm from different Barium
isotopes
138Ba
? Polarization plane
Counts kHz
PMT
137Ba F5/2
136Ba
Frequency MHz
137Ba F5/2
in Polarization plane
138Ba
Counts kHz
135Ba
PMT
Frequency MHz
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Lifetime Measurement Hanle effect
136Ba
138Ba
Counts kHz
Counts kHz

• Life time of 1P1 state
• Laser B field
• eff h/(2? gJ ? ?B1/2)
• eff 8 nsec ? 0.5sec

Magnetic Field G
Magnetic Field G
Counts kHz
Counts kHz
136Ba
138Ba
Magnetic Field G
Magnetic Field G
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Intercombination line 1S03P1
3 2 1
Creation of intense beam of meta-stable D-state
atoms
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FM Saturated absorption spectroscopy of I2
(almost one line/5GHz from 500-900nm)
w90.5kHz
ff0f1 Sin(wt)
Reference Line P(52)(0-15) transition
To Beat note
599 MHz away from 1S03P1 in 138Ba
Lock point
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1S03P1 transition in an External Magnetic field
?? gJ µ mJ B ??IS 138Ba136Ba 108.5 (3) MHz
2.3 MHz (FWHM)

• Decay rate
• Branching into 3D States

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Competitors
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Radium

• Promising candidate for experimental EDM searches
• Production of 213Ra at KVI this year at new TRI?P
  Facility
• Spectroscopy is indispensable
• Lifetimes and Hyperfine Structure
• Development toward trapping with Barium
• EDM and Parity violating effects are strong

Next year more about it
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Producing light for Ra 1S0-1P1 transiton

• Second harmonic generation in linear cavity
  using KNbO3 (b-cut, 19) 3 or 5mm
• temperature tunable and high efficiency
• Wavelength tunable from 480 nm (10C) to 490 nm
  (40C)

Blue output
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Outlook
Laser Cooling of Barium

• Diode Laser for 1P11D2 transition _at_1500nm and
  for 1P13D2 and 1P13D1 transitions
  _at_11301108nm)
• Towards Radium
• Laser _at_482.5nm for 1S01P1 transition by
  frequency doubling
• TiSapp Laser
• Production of Radium at TRIµP by end of 2004
• Spectroscopy in a Radium beam

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What are we looking for

• Dont get me wrong
• We have already great understanding (as a
  community)
• Too many free parameters
• Explain structure of physical world
• Phenomenology
• Are there basic building blocks of nature (most
  of us believe so)

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EDM? Why? What?

• MDM sure, and Maxwell unified electricity and
  magnetism a long time ago.
• So, why should EDM be zero?
• What is this great cancellation mechanism
• Electric monopole is OK, so where is the magnetic
  monopole? Can we search for it as well?

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Interpretation of EDM

• What happens when one of us observe it? Well,
  assuming that the rest believes it.
• Different length/energy scale on which we observe
  substructure -gt same theory, but more parameters
• What is an effective theory? Acknowledges already
  that is is not fundamental
• Can we get to the fundaments of Physics?

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Fundamental Symmetry Test

• C Charge Conjugation
• P Parity
• T Time Reversal
• New facilities for radioactive beams
  worldwide.Uncharted territory of on the nuclear
  chart
• is there something new? Parity nonconservation
  in atoms ?-decays

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How

• Atomic physics methods for control of
• Deviation from expectations can indicate new
  physics
• Examples Precision measurements and fundamental
  constantParity violation
• Long series of measurements