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Probing Lorentz invariance and other fundamental symmetries in

W.Heil. Probing Lorentz invariance and other fundamental symmetries in 3He/ 129 Xe clock-comparison experiments. Outline:. Features of frequency standards and clocks. 3 He/ 129 Xe „ spin “- clock. 3 He/ 129 Xe clock-comparison experiments. Conclusion and outlook.

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Probing Lorentz invariance and other fundamental symmetries in

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  1. W.Heil Probing Lorentz invarianceandother fundamental symmetries in 3He/129Xe clock-comparisonexperiments Outline: • Features offrequencystandardsandclocks • 3He/129Xe „spin“-clock • 3He/129Xe clock-comparisonexperiments • Conclusionandoutlook

  2. A. Schawlow : “Never measureanything but frequency!” Since Galileo Galilei and Christiaan Huygens invented the pendulum clock, time and frequency have been the quantities that we can measure with thehighestprecision. Counter FrequencydividerOscillator minute/hourhand pendulum  10 ms / day drivingweight

  3. Currentaccuracy: Microwave: 6 x 10-16 Optical : 3 x10-17  1 ns / day Stablefrequency Localoscillator sensitivity (absolute scale):  mHz better: referencetransitionat f  1 Hz with f /f  10-14  „nuclearspin -clock“

  4. Clockbased on nuclearspinprecession „ spin-clock“ detector signal (a.u.) (ms )

  5. Spin-clock: Detectionofspinprecession: • long spin coherence times T2*> 1 day @ low magnetic • fields (T) & low gas pressures (mbar) • at B0< 0.1 T, the SNR of a SQUID magnetometer exceeds • the SNR of conventional NMR spectrometers based • on Faraday induction to detect the signal. • intrinsic noise of SQUID:  1 fT/Hz • no feedback coupling between detector • and spin sample

  6. Accuracy of frequency determination: Fourier width # datapoints • If the noise w[n] is Gaussian distributed, the Cramer-Rao Lower Bound (CRLB) sets the lower limit on the variance example: SNR = 10000:1 , = 1 Hz ,T= 1 day

  7. 3He/129Xe „spin“-clock n = -1.913 K He = -2.1276 K Xe= -0.7779 K Xe129 He3 J 

  8. 3He (4.5 mbar ) 6 cm BMSR 2, PTB Berlin The 7-layered magnetically shielded room (residual field < 2 nT) LTc-SQUID J. Bork, et al., Proc. Biomag 2000, 970 (2000). magneticguidingfield 0.4 T (Helmholtz-coils)

  9. 3He freespin-precessionsignal Note: Atpresent, theXespin coherence time T2* is limited to due to wall relaxation SQUID Signal: d parameters: pHe= 4.5 mbar ; PHe= 15% R =2.9 cm; d = 6cm 4 h < T2*< 6 h R

  10. 0 5 1 0 1 5 2 0 129Xe 3He / 129Xe clockcomparisontogetrid ofmagneticfielddrifts 406.68 drift ~ 1pT/h B [nT] 406.67   10-5 Hz/h 406.66 t [h]  3He (13 Hz) (4,7 Hz) !

  11. Subtractionofdeterministicphaseshifts I. Earth‘srotation  = He- He / Xe Xe rem =  - Earth II. + (t)spin-coupling Phase residuals rem

  12. The detection of the free precession of co-located 3He/129Xe sample spins can be used as ultra-sensitive probe for non-magneticspin interactions • Searchfor a Lorentz violatingsiderealmodulation • oftheLarmorfrequency • Searchforspin-dependentshort-rangeinteractions • Searchfor EDM of Xenon • …

  13. Searchforviolationof Lorentz invariance Michelson (1881,Potsdam) Michelson&Morley (1887,Cleveland) E Fundamental theory (non-commutativegeometry, strings, varyingcouplings, … ? Planck scale  Issue: presentlynocompleteand realistic fundamental theory ? low-energy world Low-energyeffectivetheory (SME) Idea: - examinemanifistationsof Lorentz/CPT violatingvacuum - construct all possiblemodificationsto SM Advantage: describes all low-energyeffectsof Lorentz violation

  14. Standard-Model Extension A. Kostelecky and C. Lane: Phys. Rev. D 60, 116010 (1999) Modified Dirac equationfor a freespin ½ particle (w=e,p,n) standard DE CPT violating CPT preservingterms Lorentz violatingterms Doppler-shift Cs- fountain Torsion pendulum Antihydrogen spectroscopy Astrophysics Hg/Cs comparison UCN/Hgcomparison He/Xe maser K/He co-magnetometer G. Saathoff et al., PRL 91 (2003) 190403 Experimental access: Wolf et al., B.Heckel et al. PRD 78 (2008) 092006  clock comparison experiments couplingstrength

  15. Coupling of spin to background field: C  LAB cosmic microwave background v = 368 km/s Zeeman LV Tdip 3.3 mK

  16. Searchfor a siderealmodulationoftheweightedphasedifference rem = He - He / Xe Xe- Earth rem s= 2/TSD= 2/(23h:56m:4.091s).

  17. Results of 2-fit for the sidereal phase amplitudes ac and as together with their correlated and uncorrelated 1-errors (2nd row). • To demonstrate the strong dependence of the correlated error on s , corresponding fit results are shown for multiples of s: ’s = gs . Phaseamplitudeofthe siderealmodulation: Phase residualswith fit-resultsfor

  18. In termsoffrequency: (95% C.L.) Kostelecky et al. , Phys. Rev. D 60, 116010 (1999) (X,Y,Z) non-rotating frame with Z along Earth‘s rotation axis Lab-frame with quantization axis z free neutron: PTB Berlin: n : µ = -1.913 µK = 52,51640 north Schmidt-Model = 280 (north-south) 3He: µ = -2.1276 µK 129Xe: µ = -0.7779 µK

  19. Ourresult(submittedto PRD) Torsion pendulum B.R.Heckel et al., PRD 78 (2008) 092006 • Spin maser experimentswith3He and129Xe ( D.Bear et al., PRL 85 (2000) 5038 ) • K-3He co-magnetometer • (T.M.Brown et al.,arXiv:1006.5425; 2010)

  20. Searchfor a newpseudoscalarboson (Axion-likeparticle) Gerardus 't Hooft,: QCDhasa non-trivial vacuumstructurethat in principlepermits CP-violation fromneutron EDM weget: Original proposalforAxion ( R. Peccei, H.Quinn PRL 38(1977),1440) aspossiblesolutiontothe „Strong CP Problem“ thatcancelsthe CP violatingterm in the QCD Lagrangian Modern interest: Dark Matter candidate. All couplingsto matter areweak Axions, iftheyexist, will beverylightand will mediate a macroscopic CP- force energyscale P.Q.-symmetry isspontaneouslybroken

  21. Axionsgenerated in thesun Laboratory axions Polarised laser through vacuum in a strong magneticfield (PVLAS) AXION SEARCHES usingthe PrimakoffEffect Galacticaxions Tunable resonant cavity in magnetic field coupled to a ultra low noise microwave receiver ADMX, CARRACK 8 Tesla

  22. If axions are dark matter, they are a relic of the early universe. A particular scenario coupled with the requirement that the axion mass density not severely overclose the universe results in a lower bound to the axion mass. • CurrentAxionSearch Experiments • Solar AxionTelescope – „CAST“ • Dark Matter AxionSearch – „ADMX“ • Vacuum Optical Properties –“PVLAS“ etc. • Photon Disappearance Experiments • New Force Search – Torsion Pendulums, etc. CAST

  23. 3He 3He Most recentshort-rangemacroscopicforcetests He He ( 3He ) ( N ) with

  24. How to measure? z-axis ( B-field ) D d

  25. Lay-out of experimental setup (Pb-glass)

  26. Dewar housingtheLTc-SQUIDs Pb-glasscylinder 3He/129Xe cell

  27. Ø 57 mm H = 81 mm Density = 3.9 g/cm3 Lead glasssamples

  28. Magneticfield(measured via theHe spinprecessionsignal ) in presenceof a conductor ( aluminiumcylinder : diameter56 mm, length 70 mm) removal of aluminium block paramagneticeffects Johnson noise

  29. Falseeffects : Barometricformula : h SHe B0 x x SXe assume:

  30. B0 Right sample (8 hours): Δ = 10.6 ± 1.7 nHz∝ΔB = 0.33 ± 0.05 fT Left sample (8 hours): Δ = 9.7 ± 1.7 nHz∝ΔB = 0.30 ± 0.05 fT =>  = ½ (Δright sample - Δleft sample ) = 0.9 ± 1.2 nHz Analysis: Average potential <V*()> was calculated numerically for cell sizes diameter 6 cm x length 6 cm, gap of 3 mm between cell inner volume and lead glass cylinder (diameter 57 mm x length 81 mm ) Fromthemeasuredvalueof we get gSgP < 4 (2π)2 m3He / (NV ħ <V*()>)

  31. September 2010 runat PTB-Berlin: Expectedsensitivityrangewith BGO(=7.9 g/cm3), a gapbetween 0.1 – 1 mm, and 3 weeksofdatataking 3He/129Xe BGO

  32. Conclusionand Outlook • 3He , 129Xe clocksbased on freespinprecession •  longspincoherencetimes (so far limited by T1,wall) • Magnetometry magnetometerfornEDMexperiments • Clockcomparison LV-SME (Kostelecky): newlimits on theboundneutron !!! Improvementsstronglydepend on increaseof T2,Xe !!!

  33. Short rangespin-dependentinteraction: J.E.Moody, F.Wilczek PRD 30 (1984) 130 First results (16 h run) : newupperlimitsforgsgp in therange 10-3 m <  < 10-1m Improvements: * BGO ( =7.9 g/cm3) insteadofPb-glass (=3.9 g/cm3) (Sept.2010 run) * gap: < 1 mm * Longermeasurementtimes * Longer T2,Xe M.Rosenberry et al., PRL 86 (2001)22 129Xe electricdipolemoment: Proposal: accuracy in measuringfrequencies:

  34. 3He/129Xe clockcomparisonprobing fundamental symmetries • InstitutfürPhysik, Universität Mainz: • C. Gemmel, W. Heil, S. Karpuk, Y. Sobolev, • K. T. • Physikalisch-Technische-Bundesanstalt, Berlin: • M. Burghoff, W. Kilian, S. Knappe-Grüneberg, • W. Müller, A. Schnabel, F. Seifert, L. Trahms • PhysikalischesInstitut, Ruprecht-Karls-Universität Heidelberg: • U. Schmidt K.Tullney

  35. Field drifts 2 AllanStandard Deviation i i+1  [s]

  36. ASD ofphaseresiduals

  37. Gain in sensitivitybyreducingthegap Pb-glass 3He/129Xe 3 mm

  38. Feedback looptogetlongcoherencetimes … ( Cs-Magnetometer, Maser, … ) • but … • frequencyshifts due to • feedbackphaseerror • lightshift • …

  39. …reemission of fluorescence light LASER absorption … …transfer of angular momentum 5 p1/2 = 1 – (2/3)n 1/3 2/3 5 s1/2 m = -1/2 m = +1/2 N(1/2) – N(-1/2) P = N(1/2) + N(-1/2) T1 Optical Pumping Bo Rb-pumping + rate equation:

  40. Rb 3He 3He 3He* 3He 3He* Optical Pumping of 3He history : ●Spin exchangewithopticallypumpedRb-vapour ( SEOP ) ( Bouchiat et al., Phys. Rev. Lett. 5 (1960) 373 ) pHe 1-10 bar ●Optical pumping of metastable 3He*-atoms ( MEOP ) ( Colegrove et al., Phys. Rev. 132 (1963) 2561 ) pHe 1 mbar

  41. MEOP: Metastabilty Exchange Optical Pumping L.D. Schearer 3He : 1 mbar 3He* 1ppm

  42. Transverse Relaxation: T2* Cates; Schaefer; Happer: Phys. Rev. A 37, 8 (1988) absolute gradient → low magn. field (B0 ≈ 1 T) size: R => 3cm longitudinal relaxation time T1(He) > 100 h diffusionconst. D ~ 1/p → lowpressure (p ~ mbar) SQUID Signal: d R

  43. J.Opt.Soc.Am. 28(1938)215 G. Saathoff et al., PRL 91 (2003) 190403

  44. Laser A Laser P β (moving clock) metastable7Li+ - ions Lamb dip TSR (HD) : ß = 0.064 ESR(GSI) : ß = 0.34 Ch.D.Lane, PRD 72 (2005) 016005

  45. Fundamental physicstestsusingRband Cs fountains Wolf et al., Observable freeof 1st order Zeeman-effect

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