Collaborator ==============================

Transcription

1 RI Collaborator ==============================

2 20 CKM : 100 GeV (Plank scale): GeV

3 EDM Time: t -t Spin: s -s EDM: d d d 0 T-violation CP-violation CPT theorem Standard Model (SM) : Predicted EDM is about 10 5 smaller than the present experimental upper limit Beyond the SM : Detectable EDM EDM CP

4 CP EDM E W W f L e +i f e -i f L CKM d n = ecm QCD vacuum angle d θ ecm n ~ f E ~ f One loop level EDM f L e φ γ ~ i e φ + i L R f R

5 EDM EDM EDM of bare nucleon Quark EDM or Chromo EDM Neutron EDM EDM Xe, 199 Hg, Ra, Rn EDM T violating interaction in nuclei Orbital electron: j= EDM in nucleus Schiff moment Atomic EDM EDM.Rb, 133 Cs, 205 Tl, Fr EDM Electron EDM Electron EDM Enhancement Atomic EDM

6 E ext d E ext E ext E int d E ext + E int = 0 ( E + E ) 0 ext int = Schiff EDM EDM

7 potential φ ( R ) i = ( r) ρ() r eρ d R r i r d i Z R i J.S.M. Ginges, V.V. Flambaum, Phys. Rep. 397 (2004) 63 V. A. Dzuba et al., PRA 66, (2002) d r 3 r ϕ PT odd = e i j k i j k i j 6 ρ R 2Z R = 4πS δ ( R) Oijk i j k + Qij ( d ) i 6 R e 2Z 3 () r r r r d r + ( d ) ρ() r j 1 R r r i j d 3 r Schiff potential (rank 1) Octupole potential (rank 3) Schiff moment Electric octupole moment I S = e () r rr d r d () r r d r = S Z ρ 10 3 I 1 2 ρ Oijk eρ() r ri rjrk r ( riδ jk + rjδik + rkδ ij ) 3 = d r 5

8 Atomic EDM is induced by the nuclear Schiff moment S d A = R A S d(xe) = d(hg) = Schiff moment is induced by CP odd nuclear force 3 ( S / efm ) ecm 3 ( S / efm ) ecm S = R N ξ CP CP odd pion exchange is dominated by chromo EDM of quarks ξ 1 = G F 3g f m 2 πpp 0 2 πmπ ~ ~ ( d d ) d u (T. Falk et al., hep ph/ )

9 129 Xe EDM experiment in USA Gr. 1 ( 5 ) Xe S Vold et. Al., Phys. Rev. Lett. 52 (1984) Repetation of observing the decaying precession signal. λ/4 laser B prec E E E light pipe d = ( 0.3 ± 1.1) e cm PC Lock in 0 Lock in 1 Lock in Rosenberry and Chupp, Phys. Rev. Lett. 86 (2001) 22. Operation of continuous spin maser oscillation in double species (129Xe and 3He). d = (0.7 ± 3.3) e cm

10 199 Hg EDM experiment in USA Gr. 1 ( 6 ) Hg S0 Washington univ. Gr Lamoreaux et. al., Phys. Rev. Lett. 59 (1987) d = (0.7 ± 1.5) ecm : Jacobs et. Al., Phys. Rev. A 52 (1995) d = ( 1.0 ± 3.6) e cm Romalis et. al., Phys. Rev. Lett. 86 (2001) d = ( 1.06 ± 0.49) 10 Now minor improvements. d ecm 28 e cm

11 EDM Experimental upper limit from different elements In the MSSM (Minimal Super Symmetric Model) New CP violating phases θ A, θ µ are naturally considered to be O(1) M=250GeV M=500GeV M: Energy scale of SUSY breaking T. Falk et al., hep ph/

12 Expected frequency shift Assuming d = ecm B=1 G, E=+10 kv/cm z B +E B=1 G, E= 10 kv/cm z B E y ω + t x ν + = ( ) Hz ν = ( y ω t x ) Hz B +E B -E ν = Hz n cycle n+1 cycle A difference of 1 cycle in 10 9 sec. 31years 259days 2hours

13 1 P : Polarization δd PEτ NT / τ N : Number of particles T : Measurements Time τ : Spin Coherence Time E : Electric Field

14 Spin exchange with optical pumped Rb atom P > 10 % for Xe atomic density of /cm 3 Rb ~ atom/cm Xe No chemical interaction No quadrupole interaction of nucleus ( I=1/2 ) Continuous spin maser technique Transverse spin Free precession Transverse spin Spin maser state Time Time

15 W. Rb Happer, Rev. Mod. Phys. 44 (1972) P 1/ 2 D nm 5S 1/ 2 m s 1 = 2 m s 1 = + 2 Rb Rb van der Waals

16 Pyrex baking Coating Rb SurfaSil γ se PXe = PRb Xe γ + Γ se

17 Γ W = /s T W = 1050 s P = torr (10 18 /cm 3 )

18 SurfaSil

19 1. Accumulation of decaying precession δν final T T T ind = δν = = n n T T 2. Continuous spin precession total δν final 1 = δφ = T total T 3/ 2 tatal T Total

20 Spin MASER Transverse magnetic field - synchronism with spin precession - Phase : perpendicular to the transverse polarization Amplitude : proportional to the transverse polarization Polarization s growing (pumping effect) Relaxation, pumping B 0 T2 relaxation Feedback torque Polarization vector : M Feedback torque Polarization Feedback field : B fb Population inversion Feedback EM-field synchronism with emitted photon pump Zeeman level Feedback system

21 Nuclear Spin Maser (spin-coil coupling) 129 Xe polarization vector P = S /S Static field B 0 = (0, 0, B 0 ) Oscillating field B = (B x, B y, 0) B FB L B 0 dp P follows the Bloch equations: x d t dp y d t dp z d t Px = γ ( PB y 0 PB z y) T2 Py = γ ( PB z x PB x 0 ) T Pz = γ ( PB x y PB y x) + ( P0 Pz) G. T 2 1,, relaxation term Pumping term I npq C γ B = 1 0 LC M.G. Richards, JPB 21 (1988) 665: 3 He spin maser T. Chupp et al., PRL 72 (1994) 2363: 129 Xe spin maser B () t P () t x B () t P () t y y x 1 γ 2 2 ηµ 1 0 Q hi[ n] P0 > T2

22 Nuclear spin maser at low frequency ( low B 0 -field ) Low magnetic field B 0 ( < 0.1 G ): low field fluctuation introduce of high precision magnetometer B 0 < 0.1 G ν 0 < 100 Hz spin precession : optical detection Continuous oscillation through the feedback system Detection of Xe spin direction ( with probe laser) B 0 mg Probe laser beam Feedback coil Phase shifter Producing a transverse magnetic field (delayed by 90 in phase to precession signal) Nuclear spin Photo diode Pumping laser beam Lock in detection PLA 304 (2002) 13. A. Yoshimi et al.

23 Optical detection of nuclear spin precession Transverse-polarization transfer : Rb atom Xe nuclei (re-polarization) Rb dp dt Rb Xe = γ se( PXe PRb ) ΓsdP = γ '[ Xe]( P ) Rb Xe PRb ΓsdPRb γ [Xe] = /s, Γ sd = 0.2 /s Time constant of spin transfer: 10-4 s Precession frequency of < khz Probe laser beam : single mode diode laser (794.7nm) P Rb 0.3 ms (ms) Xe After half-period precession Xe Circular polarization (modulated by PEM) Xe Rb Xe Xe Rb Xe

24 Experimental apparatus Pumping LASER Tunable diode laser λ = nm ( Rb D1 line ), λ = 3 nm Output: 18 W Solenoid coil (for static field) B 0 = 28.3 mg ( I = 3.58 ma) Magnetic shield (3 layers ) Parmalloy Size : l = 100 cm, d = 36, 42, 48 cm Shielding factor : S = 10 3 Si photo diode Freq. band width: khz NEP: W/Hz Probe LASER PEM Mod. Freq. 50 khz Heater T cell = 60 ~ 70 Xe gas cell 18 mm Enriched 129 Xe : 230 torr Rb : ~ 1 mg Pyrex spherical grass cell SurfaSil coated Tunable diode laser with external cavity λ = nm ( Rb D1 line ), line width 1MHz Output: 50 mw

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26 129 Xe free precession signal (FID signal) Static magnetic field B 0 = 28.3 mg (ν(xe)=33.5 Hz) 90 RF pulse 33.5 Hz, t = 3.0 ms, B 1 = 70 mg ) Transverse relaxation T 2 = 350 s Signal (mv) T s Time (s) 0.16 Frequency: 0.00 ν beat = ν prec ν ref = Hz

27 B 0 = 30.6 mg ν 0 = 36.0 Hz Signal (V) Time (s) transient steady-state oscillation

28 Various transients depending on the feedback strength Feedback Gain 4 µg/0.1mv 10 µg/0.1mv 14 µg/0.1mv Signal (mv) Signal (mv) Signal (mv) µg/0.1mv Signal (mv) Time (s)

29 (Hz) τ 3/ 2 δν τ 1 δν τ (s) Maser beat frequency (mhz) 9 3x10 4 s s maser Allan = 29 Hz Run#

30 Rb Linear polarized light D. Budker et al.,pra 62 (2000) g F µ B Bz γ ϕ = 2g F µ B B 1+ γ z l 2 2l0 k B Alkali vapor(rb) Faraday rotation rad/g, G/ Hz (B < 0.1G) γ 0 n 1+ 2πχ ± ( ω) 0 2 ( ω ω0 m g F µ BBz ) + iγ 0 ϕ B Yu.P. Malakyan et al.,pra 69 (2004)

31 D. Budker et al., Rev.Mod.Phys. 74 (2002) Ω M =1 khz B=0.7 mg alignment

32 Probe laser Linier polarizer λ 2 Shield cell Photo elastic modulator Linier polarizer Photo diode Ref. cell Photo diode Solenoid Ref. in 100 khz PEM driver Sig. in Fabry Perot interferometer Lock in regulator Lock in Amp AC Laser control 0.04 Feedback modulation Laser stabilization system (mrad) (G)

33 Expected sensitivity for EDM experiment Installation of atomic magnetometer into low frequency spin maser Conceptual setup sensitivity : G/ Hz δb G ( δν(xe) 0.1 nhz ) Main source of frequency noise interaction with Rb atomic spins (10 9 /cc) P(Rb) 0.01 % ( re-polarization from Xe ) ν(xe) 0.2 nhz (δt 0.01 C) (E=10kV/cm) Probe light (Magnetometer) d(xe) = ecm