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, (2002). Enhancements favours Ra: Nuclear Structure Atomic Structure Can we exploit natures offer? Road to edm with Radium

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.A (2000) EDMs violate - Parity - Time Reversal

EDM Searches point particles e, ,  nucleonsn atomsTl, Cs, Hg, Ra Molecules PbO, YbF, TlF Any object will do  need guidance by theory What is the source for an EDM?

EDM Now and in the Future 1.6  Start TRI  P 199 Hg Radium potential d e (SM) <

Fortson Group Seattle, Washington d < e cm 199Hg Experiment, M. Romalis

From M. Romalis Fortson Group Seattle, Washington

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

Sensitivity P Polarization  Efficiency N Number of particles per second T Measurements Time  Spin Coherence Time Paramenters 1 P  N T/  ) 1/2 S =

TRI  P Radium Permanent Electric Dipole Moment Benefits of Radium near degeneracy of 3 P 1 and 3 D 2 near degeneracy of 3 P 1 and 3 D 2  ~ enhancement  ~ enhancement some nuclei strongly deformed spin > 1/2 some nuclei strongly deformed spin > 1/2  nuclear enhancement  nuclear enhancement50~500 6 Ra also interesting for weak interaction effects Anapole moment, weak charge (Dzuba el al., PRA 6, )

Enhancement of EDM Heavy Atoms ~ Z 2 (R N /R A ) Induced Dipol Moment  Polarizability in nucleus as well as atomic shell Example: Tl ~ -585, Fr ~ 1150, Ra ~ D A = + c.c.  E nl – E n’(l+1) n’

Experimental Aspects Cells Cells  high density motional fields average to zero long coherence times Beams Beams  ultra high vacuum leakage current suppression higher electric fields coherence time limited by length of beam Traps ?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 SystemsNew Systems New production facilities for short lived isotopes

Ion Catcher RFQ Cooler Atom Trap Particle Physics Production Target Magnetic Separator MeVmeVkeVeVneV AGOR cyclotron TRI  P - Trapped Radioactive Isotopes:  -laboratories for fundamental Physics Beyond the Standard Model TeV Physics EDM/  -decay

Cold Radionuclides Work Ion traps have been successful Physics Program: mass measurements nuclear spectroscopy correlations 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 …

Target Gas filled Separator QD 208 Pb beam T1 Trap Experiments DD Isotope TRI  P KVI Separator commissioned with Na production Ra at TRI  P Facility in couple of month

AGOR Cyclotron Adaptating to New Challenges Heavy Ion Beams Heavy Ion Beams  e.g. 208 Pb  e.g. 208 Pb new sources new sources new injection channel vacuum improvement High Power (TRI  P would appreciate 1 kW) High Power (TRI  P would appreciate 1 kW) improved extraction beam stops beam monitoring radiation safety Expect Ra/kW beam AGOR

TRI  P x-ray counts [arb.] x-ray energy [channels] raw data fitted x-ray spectra extracted Fr x-rays A. Rogachevsky, H. Wilschut, S. Kopecky, V. Kravchuk, K. Jungmann + AGOR team First TRI  P Tests 15 N Tl  213 Ra + 7n 213 Fr C Tl C N Ra Fr x-rays Production Test 213 Ra Expected Production Rates ~ 10 7 /s with 1kW primary beam

Radium Spectroscopy What do we know?

Radium Spectroscopy Data Radium Discharge analyzed with grating spectrometer Ebbe Rasmussen, Z. Phys, 87, 607, 1934; Z. Phys, 86, 24, Resolution ~ 0.05 A, 99 lines, absolute accuracy [A][A] Corrections in deduces energy levels 1S0-1P1 1S0-1P1 1S0-3P11S0-3P1 H.N. Russel, Phys. Rev. 46, 989 (1934) [A][A] Similar to Barium  identification as alkaline earth element

482.7 nm 714 nm 7s 2 1 S 0 7s 7p 1 P 1 7s 7p 3 P 7s 6d 1 D 2 7s 6d 3 D nm 1488 nm  2.8  m Transitions in Radium Collinear laser spectroscopy 1 S 0 – 1 P 1 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) Spectroscopy of P and D states Lifetime measurement Energy level spacing Hyperfine structure To do list: According to NIST Database

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 KVI RIMS  Trace analysis Next Species Ba Ra

Cooling and Trapping Type Energies Scale Slowing1000 m/s Zeeman, white light, chirped laser, bichromatic force 100 meV MOT100 m/sinhomogeneous B-Field Optical Molasses10 m/s, 1 K no B-Field FORT> 1 mKno B-Field Magnetic Trap0.7 K/T/  B inhomogeneous B-Field Cryogenic Buffer 0.7 K/T/  B inhomogeneous B-Field Gas Loading Trap losses: background gas ~ mbar optical traps  not closed cycling scheme

Preliminary Transition Rates as calculated by K. Pachucky (also by V. Dzuba et al.) Trappist’s View 3*10 4 s *10 8 s -1 7s 2 1 S 0 7s 7p 1 P 1 7s 7p 3 P 7s 6d 1 D 2 7s 6d 3 D *10 5 s -1 3* *10 6 s -1 4*10 3 s -1 Cooling Transition 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 View 3*10 4 s *10 8 s -1 7s 2 1 S 0 7s 7p 1 P 1 7s 7p 3 P 7s 6d 1 D 2 7s 6d 3 D *10 5 s -1 3* *10 6 s -1 4*10 3 s -1

Trappist’s View 7s 6d 3 D *10 8 s -1 7s 2 1 S 0 7s 7p 1 P 1 7s 7p 3 P 7s 6d 1 D *10 6 s -1 Consequences for Laser Cooling with 1 S P 1 Smaller Enhancement of EDM Longer Lifetime of 3 D 2 in E-Field Energy levels calculation 3 D-States are lower J. Biron & K. Pachucky (priv. Comm.) 7s 6d 3 D 1 2 3

Radium Spectroscopy Laser Cooling Metastable Beam Barium

Heavy Alkaline Earth Element: Barium  – 8.4nsec I s =14mW/cm Life time measurement Hyperfine structure Laser cooling of barium Develop trapping strategy nm 6s 2 1 S 0 6s 6p 1 P 1 6s 5d 1 D 2 6s 6p 3 P nm 1499 nm 6s 5d 3 D  3  m 1108 nm  – 1.4 µsec I s =30µW/cm nm Ideal testing ground: No report yet on laser cooling and trapping!

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

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

Lifetime Measurement: Hanle effect Life time of 1 P 1 state Laser || B field  eff = h/(2  g J   B 1/2 )  eff = 8 nsec  0.5sec 138 Ba 136 Ba 138 Ba 136 Ba Counts [kHz] Magnetic Field [G]

553.7 nm nm 6s 2 1 S 0 6s 6p 1 P 1 6s 6p 3 P 1 6s 5d 3 D  3  m 1.4 µsec 8.4 nsec 40% 60% Creation of intense beam of meta-stable D-state atoms Intercombination line 1 S 0 – 3 P 1

FM Saturated absorption spectroscopy of I 2 Diode Laser nm I 2 Oven (560ºC) M1 M3 BS PD Lock-In Amp Feedback Control VCO /4 AOM To Beat note Lock point Reference Line P(52)(0-15) transition f=f 0 +f 1 Sin(wt) w=90.5kHz 599 MHz away from 1 S 0 – 3 P 1 in 138 Ba (almost one line/5GHz from nm)

1 S 0 – 3 P 1 transition in an External Magnetic field  = g J µ m J B  IS = 138 Ba– 136 Ba= (3) MHz 2.3 MHz (FWHM) Decay rate Branching into 3 D States

Competitors

Radium Promising candidate for experimental EDM searches Production of 213 Ra 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

Producing light for Ra 1 S P 1 transiton Second harmonic generation in linear cavity using KNbO 3 (b-cut, 19°) 3 or 5mm; temperature tunable and high efficiency Wavelength tunable from 480 nm (10°C) to 490 nm (40°C) M1 M2 Telescope BS Split PD PZT R=-50mm, HR485 nm & 970 nm Faraday Isolator Ti:Sapp Dichroic Mirror KNb0 3 HR AR Blue output

Outlook Diode Laser for 1 P 1 – 1 D 2 and for 1 P 1 – 3 D 2 and 1 P 1 – 3 D 1 Towards Radium for 1 S 0 – 1 P 1 transition by frequency doubling Ti:Sapp Laser Production of Radium at TRIµP by end of 2004 Spectroscopy in a Radium beam Laser Cooling of Barium

What are we looking for Don’t 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)

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?

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 -> 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?

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

How Atomic physics methods for … control of Deviation from expectations can indicate new physics Examples: Precision measurements and fundamental constant Parity violation Long series of measurements