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Neutral atom nuclear EDM Experiments

Neutral atom nuclear EDM Experiments. Investigating Radium. Lorenz Willmann KVI, Groningen. ECT* Trento, June 21-25, 2004. Outline. Nuclear edm searches in neutral atoms ( 199 Hg) Are there other systems Schiff Moment in Hg, Xe, Rn, Ra, Pu, TlF Dzuba, et al., PRA 66, 012111 (2002).

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Neutral atom nuclear EDM Experiments

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  1. Neutral atom nuclear EDM Experiments Investigating Radium Lorenz Willmann KVI, Groningen ECT* Trento, June 21-25, 2004

  2. 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 Structure Atomic Structure • Can we exploit natures offer? Road to edm with Radium

  3. Violation of T-Symmetry H= -(d E+µ B) I/I d - electric dipole moment µ- magnetic dipole moment I - Spin Limit for nuclear EDM Hg d< 2.1 x 10–28 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) EDMsviolate - Parity - Time Reversal

  4. EDM Searches Any object will do  needguidance by theory • point particles e,, • nucleons n • atoms Tl, Cs, Hg, Ra • Molecules PbO, YbF, TlF What is the source for an EDM?

  5. EDM Now and in the Future 1.610-27 • • 199Hg Radium potential Start TRIP de (SM) < 10-37

  6. 199Hg Experiment, M. Romalis Fortson Group Seattle, Washington d < 2.1 10-28 e cm

  7. Fortson Group Seattle, Washington From M. Romalis

  8. Electric Dipole Moment: e h 2 m c d =  J d = 10-25 e cm E = 100 kV/cm  w = 1.5 *10-5 rad/s Measure EDM Prepare Ensemble in Spin State J Apply Electric Field E Determination of Ensemble Spin Average Precession Frequency:  = d x E

  9. S= 1 Pe t ( N T/t )1/2 Sensitivity Paramenters P Polarization e Efficiency N Number of particles per second T Measurements Time t Spin Coherence Time

  10. TRImP Radium Permanent Electric Dipole Moment • Benefits of Radium • near degeneracy of 3P1 and 3D2 •  ~40 000 enhancement • some nuclei strongly deformed spin > 1/2 •  nuclear enhancement • 50~500 6 • Ra also interesting for weak interaction effects • Anapole moment, weak charge • (Dzuba el al., PRA 6, 062509)

  11. < nl | -de(-1)  E | n’(l+1) > < n’ (l+1) | -er | nl > DA= + c.c. Enl – En’(l+1) n’ 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

  12. 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

  13. TRIP - Trapped Radioactive Isotopes:-laboratories for fundamental Physics Production Target Magnetic Separator Ion Catcher RFQ Cooler Atom Trap Particle Physics Beyond the Standard Model TeV Physics EDM/-decay AGOR cyclotron MeV keV eV meV neV http://www.kvi.nl/~trimp/web/html/trimp.html

  14. Cold Radionuclides Work • Ion traps have been successful Physics Program: mass measurementsnuclear spectroscopycorrelations 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 …

  15. Isotope production @ 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

  16. AGOR Cyclotron AGOR • 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 107213Ra/kW beam

  17. TRImP FirstTRImPTests 15N +205Tl  213Ra + 7n 213Fr Ra Fr x-rays N CTlC Production Test 213Ra 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

  18. Radium Spectroscopy What do we know?

  19. [A] [A] Similar to Barium  identification as alkaline earth element 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)

  20. Transitions in Radium 7s 7p 1P1 1488 nm  2.8 m 1438 nm 7s 6d 1D2 2 1 0 3 2 1 7s 6d 3D 7s 7p 3P 482.7 nm To do list: • Spectroscopy of P and D states • Lifetime measurement • Energy level spacing • Hyperfine structure 714 nm 7s2 1S0 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)

  21. KVI RIMS Trace analysis Ba Ra Next Species 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

  22. Type Energies Scale Slowing 1000 m/s Zeeman, 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/mB inhomogeneous B-Field Cryogenic Buffer 0.7 K/T/mB inhomogeneous B-Field Gas Loading Cooling and Trapping Trap losses: background gas ~1 s @ 10-9 mbar optical traps  not closed cycling scheme

  23. 7s 7p 1P1 Repumping necessary 1*105 s-1 3*105 3*104 s-1 Repumping 7s 6d 1D2 2 1 0 3 4*103 s-1 2 1 7s 6d 3D 2.2*108 s-1 7s 7p 3P Cooling Transition Weaker line, second stage cooling 1.6*106 s-1 1.4*10-1 s-1 7s2 1S0 Trappist’s View Preliminary Transition Rates as calculated by K. Pachucky (also by V. Dzuba et al.)

  24. 7s 7p 1P1 1*105 s-1 3*105 3*104 s-1 7s 6d 1D2 2 1 0 3 4*103 s-1 2 1 7s 6d 3D 2.2*108 s-1 7s 7p 3P 1.6*106 s-1 7s2 1S0 Trappist’s View Preliminary Transition Rates as calculated by K. Pachucky (also by V. Dzuba et al.)

  25. Energy levels calculation 3D-States are lower J. Biron & K. Pachucky (priv. Comm.) 7s 7p 1P1 7s 6d 1D2 2 1 0 3 3 2 2 1 1 7s 6d 3D 7s 6d 3D 2.2*108 s-1 7s 7p 3P 1.6*106 s-1 7s2 1S0 Trappist’s View • Consequences for • Laser Cooling with 1S0-3P1 • Smaller Enhancement of EDM • Longer Lifetime of 3D2 in E-Field

  26. Radium Spectroscopy Barium • Laser Cooling • Metastable Beam

  27. 6s 6p 1P1 1130 nm 6s 6p 3P 2 1 0 1499 nm 6s 5d 1D2  3 m 1108 nm 553.7 nm 6s 5d 3D 791.3 nm  – 1.4 µsec Is=30µW/cm2 6s2 1S0 Heavy Alkaline Earth Element: Barium Ideal testing ground:  – 8.4nsec Is=14mW/cm2 • Life time measurement • Hyperfine structure • Laser cooling of barium • Develop trapping strategy 3 2 1 No report yet on laser cooling and trapping!

  28. Optical fiber from 791.3 nm diode laser Collimator B PMT Ba Oven 500C /2 PD BS Power Stabilization M1 Dye Laser 553.7 nm AOM Coherent 699 Single mode dye laser First Steps Verdi pump at 532 nm

  29. Fluorescence at 553.7 nm from different Barium isotopes 138Ba  Polarization plane Counts [kHz] PMT 137Ba F=5/2 136Ba Frequency [MHz] 137Ba F=5/2 in Polarization plane 138Ba Counts [kHz] 135Ba PMT Frequency [MHz]

  30. 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]

  31. 6s 6p 1P1 8.4 nsec 6s 6p 3P 60% 1.4 µsec 1  3 m 553.7 nm 6s 5d 3D 791.3 nm 40% 6s2 1S0 Intercombination line 1S0–3P1 3 2 1 Creation of intense beam of meta-stable D-state atoms

  32. FM Saturated absorption spectroscopy of I2 Lock-In Amp Feedback Control PD VCO M1 /4 AOM I2 Oven (560ºC) BS Diode Laser 791.3 nm M3 BS (almost one line/5GHz from 500-900nm) w=90.5kHz f=f0+f1 Sin(wt) Reference Line P(52)(0-15) transition To Beat note 599 MHz away from 1S0–3P1 in 138Ba Lock point

  33. 1S0–3P1 transition in an External Magnetic field  = gJµ mJ B IS = 138Ba–136Ba= 108.5 (3) MHz 2.3 MHz (FWHM) • Decay rate • Branching into 3D States

  34. Competitors

  35. 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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