W. Heil He/Xe Clock-Comparison Experiments PSI Limit on Lorentz and CPT Violation Using a Free Precession 3He/129Xe Co-magnetometer Background fields (tensor fields) give preferred direction e.g. rest frame of CMB  talk of Ralf Lehnert Outline:  Experimental searches for Lorentz and CPT Violation  Features of 3 He/ 129 Xe „spin“-clock  Conclusion and outlook  Results from 3 He/ 129 Xe clock-comparison experiment

Michelson (1881,Potsdam) Michelson&Morley (1887,Cleveland) c(  ) = c photon sector: Traditional tests of Lorentz symmetry & special relativity 19 independent parameters Li + - ions C.Novotny et al., PR A 80 (2009) ESR at GSI relativistic Doppler effect c(v) = c

Test of constancy of c Kennedy,Thorndike 1932 Hils,Hall 1990 Braxmaier 2002 Wolf 2004 Herrmann 2009 Resonators Interferometers Year

Modified Dirac equation for a free spin ½ particle (w=e,p,n) standard DECPT violatingCPT preserving terms A. Kostelecky and C. Lane: Phys. Rev. D 60, (1999) Lorentz violating terms Standard-Model Extension Experimental access: Cs- fountain Torsion pendulum Antihydrogen spectroscopy Astrophysics Hg/Cs comparison UCN/Hg comparison He/Xe maser K/He co-magnetometer  clock comparison experiments Wolf et al., B.Heckel et al. PRD 78 (2008) matter sector - Neutron:

Topics: searches for CPT and Lorentz violations involving -birefringence and dispersion from cosmological sources -clock-comparison measurements -CMB polarization -collider experiments -electromagnetic resonant cavities -equivalence principle -gauge and Higgs particles -high-energy astrophysical observations -laboratory and gravimetric tests of gravity -matter interferometry -neutrino oscillations -oscillations and decays of K, B, D mesons -particle-antiparticle comparisons -space-based missions -spectroscopy of hydrogen and antihydrogen -spin-polarized matter * Theoretical studies of CPT and Lorentz biviolation involving -physical effects at the level of the SM, General Relativity, and beyond -origins and mechanisms for violations classical and quantum issues in field theory, particle physics, gravity, and strings Modern Tests of Lorentz violation

C Coupling of spin to background field: Zeeman LV  LAB cosmic microwave background v = 368 km/s  T dip  3.3 mK ~  T ~ GeV

F=4 F=3 133 Cs Micro-Wave f = 9.192… GHz Oscillator + Frequency divider + Counter State detection + frequency feedback accuracy (absolute scale):  f  3 µHz corresponding energy shift   1.5· GeV Atomic clock Spin clock Spin clock : reference transition at f  10 Hz with  f/f  accuracy (absolute scale):  f  1 pHz    4· GeV accuracy to trace tiny frequency shifts  6 orders of magnitude higher

3 He / 129 Xe clock comparison to get rid of magnetic field drifts 129 Xe (4,7 Hz) 3 He (13 Hz) B [nT] t [h] drift ~ 1pT/h   Hz/h B 0 ~ 1  T

(G. D. Cates, et al., Phys. Rev. A 37, 2877) (ms ) signal (a.u.) Standard NMR How to obtain long spin-coherence times in a macroscopic spin sample ? BMSR 2, PTB Berlin J. Bork, et al., Proc. Biomag 2000, 970 (2000). Motional narrowing : LT c - SQUID gradiometer noise: 10 cm (residual field : ~ 1 nT )

Data evaluation and results Fitfunction Individual runs (~24 h): Earth rotation Ramsey-Bloch-Siegert shift (  talk of U. Schmidt)

ASD plot of phase residuals Measurement sensitivity: 4 gradiometer, 7 runs Data evaluation and results

Global Fitfunction: Fitfunction Individual runs: (95% C.L.) Year 2009 data run: ~ 12 h  s = 2  /T SD = 2  /(23 h :56 m :4.091 s ).

 cos mrad  sin mrad To demonstrate the strong dependence of the correlated error on  s, corresponding fit results are shown for multiples of  s :  ’ s = g  s March 2009 subrun (shifted by 0.04 rad) 2012 data

Data evaluation and results Global Fitfunction: Fitfunction individual runs: Preliminary fit result: SME Kostelecky et al., PR D 60, (1999) Year 2012 data run: ~ 24 h

Results Kostelecky, Russell arXiv: v6 (2013) neutron Lorentz violating effect for each gas is that of a single valence neutron (Schmidt model) Tightest constrains on SME parameters on neutron sector:

Conclusion  3 He, 129 Xe spin clock based on free spin precession  long spin coherence times  ultra-sensitive probe for non-magnetic spin interactions of type:  Sensitivity (Cramer Rao Lower Bound) : spin coupling to a Lorentz- and CPT-violating background field  result (2012 data, preliminary ): Outlook  present sensitivity limited by correlated error:  increase : matter of research !  gain of measurement sensitivity ~ 100 : essentially by increasing test of SME parameters (energy range) : GeV

W. Heil He/Xe Clock-Comparison Experiments PSI Thank you for your attention Institut für Physik, Universität Mainz: C. Gemmel, W. Heil, S. Karpuk, K. Lenz Y. Sobolev, K. Tullney Physikalisch-Technische-Bundesanstalt, Berlin: M. Burghoff, W. Kilian, S. Knappe-Grüneberg, W. Müller, A. Schnabel, F. Seifert, L. Trahms Physikalisches Institut, Ruprecht-Karls-Universität Heidelberg: F. Allmendinger, U. Schmidt 3 He/ 129 Xe Clock-Comparison Experiments

backups

Change of the absolute field gradient during rotation and its effect on T 2 *

20 Limit: 60s only for T < 60s  reaches CRLB Test of CRLB via Allan Standard Deviation (ASD) Non-gaussian noise: magnetic field drifts intrinsic noise … 2 ii+1  He/Xe Clock-Comparison Experiments CPT’

SM: relativistic quantum field theory electromagnetic force weak force strong force gravitation General relativity is a classical theory, i.e., non-quantum Standard Model (SM) of particle physics Unification theories: string theory, loop quantum gravity,.. Planck scale: energy scale where gravity meets quantum physics M p ~ GeV Courtesy of C. Lämmerzahl A closer look…

Kostelecký, Perry, Pot, Samuel ’89; ’90; ’91; ’95; '00 Spontaneous Lorentz symmetry breaking in string theory e.g. Lorentz vector field makes non zero vacuum expectation value low-energy world Planck scale  GeV Background fields (tensor fields) give preferred direction e.g. rest frame of CMB D. Colladay and V.A. Kostelecky, Phys. Rev. D 55, 6760 (1997); Phys.Rev. D 58, (1998)  talk of Ralf Lehnert

Kostelecky et al., Phys. Rev. D 60, (1999) 3 He: µ = µ K 129 Xe: µ = µ K n : µ = µ K Schmidt-Model free neutron: (X,Y,Z) non-rotating frame with Z along Earth‘s rotation axis Lab-frame with quantization axis z In terms of frequency: (95% C.L.) PTB Berlin:  = 52, north  = 28 0 (north-south) PRD 82 (2010)

3 He free spin-precession signal R d SQUID parameters: p He = 1-3 mbar ; P = 10-50% R =2.9 cm; d = 6cm   B = pT Signal: Note: At present, the Xe spin coherence time T 2 * is limited to due to wall relaxation T 2 *  8 h system noise inside BMSR-2 ~ 2 fT/  Hz

He/Xe Clock-Comparison Experiments CPT’ Frequency estimation The Cramer-Rao Lower Bound (CRLB) sets the lower limit on the variance example: SNR = 10000:1, f BW = 1 Hz, T= 1 day  Correction for exponential damping of signal amplitude ( T 2 * - relaxation ) T

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

nm MEOP Polarizer Mainz: 3 He SEOP Polarizer PTB: 129 Xe He Xe N2N2 He/Xe Clock-Comparison Experiments CPT’

detector Clock based on nuclear spin precession „ spin-clock“ (ms ) signal (a.u.) (G. D. Cates, et al., Phys. Rev. A 37, 2877)

29 Nuclear spin properties: “First order” nuclear structure: Both nuclei have one unpaired neutron, which accounts for the nuclear spin. All other nucleons are paired with antiparallel spins  3 He and 129 Xe polarization Spin exchange with optically pumped Rb-vapour ( SEOP ) 3 He polarization Optical pumping of metastable 3 He * -atoms ( MEOP ) He/Xe Clock-Comparison Experiments CPT’

30 Fitting subset subset left:  2 /dof = 1.03 He/Xe Clock-Comparison Experiments CPT’

31 Subtraction of deterministic phase shifts He/Xe Clock-Comparison Experiments CPT’ a lin : earth rotation and chemical shift

32 Subtraction of deterministic phase shifts +  (t) spin-coupling a : generalized Ramsey-Bloch-Siegert-Shift  Magnetisation (self shift) b : Bloch-Siegert-Shift  Magnetisation 2 of other spin species He/Xe Clock-Comparison Experiments CPT’

33 The detection of the free precession of co-located 3 He/ 129 Xe sample spins can be used as ultra-sensitive probe for non-magnetic spin interactions of type:  Search for spin-dependent short-range interactions (axion like particles)  Search for a Lorentz violating sidereal modulation of the Larmor frequency  Search for EDM of Xenon  … Observable: He/Xe Clock-Comparison Experiments CPT’

34 Status of the 129 Xe-EDM experiment (1)Plastic housing, filled with SF 6 ; Prototype exists (2)Glass cell with silicon lids; Prototype exists (3)High voltage electrodes with cabling; Design phase, High voltage supply with leakage current detection is under construction (4)Overall design/calculations of electric field distribution, leakage current estimates are almost finished (5) Cryostat made of carbon fibre ordered; special low temperature SQUID Gradiometers ordered He/Xe Clock-Comparison Experiments CPT’

Repetition of short measurements of free precession T m : measurement time Measurement of uninterrupted precession Gain in sensitivity:

Measurement sensitivity: 129 Xe electric dipole moment EoEo  E   E  BoBo E E Then we will reach … after 100 days of data taking: from 2010 run:  = 19 1 day assume : E=2 kV/cm Observable: weighted frequency difference sensitivity limit: Rosenberry and Chupp, PRL 86,22 (2001) ecm