Observation of a large atomic parity violation effect

Transcription

1 Obsevation of a lage atomic paity violation effect in Yb K. Tsigutkin, J. E. Stalnake, D. Dounas-Faze, A. Family, V. V. Yashchuk, and Dmity Budke Univesity of Califonia, Bekeley Nuclea Science Division, LBNL PAVI June Ba Habo, Maine

2 Outline APV = Atomic Paity Violation PNC A bit of APV histoy (fom pesonal pespective) Motivation fo measuing APV in Yb Appaatus and pocedue Systematics Results: lagest APV amplitude so fa (10 2 Cs) Outlook Yb + Dy

3 Atomic PV landmaks 1959 Ya. B. Zel dovich: PNC (Neut. Cuent) Opt. Rotation in atoms 1974 M.-A. & C. Bouchiat Z 3 enhancement PV obsevable in heavy atoms Novosibisk, Bekeley discovey of PV in OR(Bi) and Stak-intef.(Tl) 1995 Boulde, Oxfod, Seattle, Pais PV measued to 1-2% in Cs, Tl, Bi, Pb 1997 Boulde 0.35% measuement, discovey of anapole moment 26 yeas 2009 Bekeley Lage APV in Yb (pesonal landmak)

4 What wee we doing all this time? Bi, diatomic molecules, Sm (Novosibisk) with L. M. Bakov and M. Zolotoev Tl (Bekeley) with E. D. Commins, D. DeMille, and M. Zolotoev Dy M. Zolotoev, D. DeMille, E. D. Commins, A.-T.Nguyen, A. Cingoz, N. Leefe Sm S. M. Rocheste Yb S. J. Feedman, C. J. Bowes, G. Gwinne, J. E. Stalnake, D. F. Kimball, V. V. Yashchuk, K. Tsigutkin, A. Family, D. Dounas-Faze,

5 Why did it take so long to detect PNC? D. A.-T. Nguyen says: it was deposited

6 Paity Violation in Yb: motivation Atomic Physics: Veification of lage pedicted atomic PV effect (x100 Cs; DeMille, Kozlov et al, Das et al) Nuclea Physics: Nuclea spin-dependent p PV anapole moments (valence neutons) Isotopic atios and neuton distibutions (6 stable isotopes; ΔN=8) 6

7 Anapole Moment f di ib i ( l ) of a cuent distibution (e.g., a nucleus) j ) ( 1 Ya. B. Zel dovich ( ) = d R j c A R 3 ) ( = R R R R k k l k k k ( ) = = d j cr R A 3 (0) 0 ) ( 1 ( ) ( ) = = d j c m R R m R A 3 3 (1) ) ( 2 1 ; ( ) = = d j a R a R A 3 2 (2) ) ( ); ( π δ T-conseving; P-violating

8 Anapole Moments 1959 Ya. B. Zel dovich, V. G. Vaks AM fist intoduced V.V. Flambaum, I.B. Khiplovich & O.P. Sushkov Nuclea AM detectable in atoms 1995 E.N.Fotson and co-wokes Tl AM small 1997 C. E. Wieman and co-wokes Cs AM detected! PNC within nucleus! pobe of weak meson couplings 8

9 Isotopic atios and neuton distibutions Atomic PV calculation eos cancel in isotopic atios Dzuba, Flambaum, and Khiplovich, Z. Phys. D 1, 243 (1986) But enhanced sensitivity to the neuton distibution ρ n () Fotson, Pang, Wilets, PRL 65, 2857 (1990) Atomic PV Neuton distibutions ib ti Fo 170 Yb- 176 Yb, Q W -100; ΔQ W (Standad Model) 6 ΔQ W (Neuton Skin) 0.1 (model dep.) 9

10 Isotopic atios and neuton distibutions: new development [PHYSICAL REVIEW C 79, (2009)] Neuton-skin effects in diffeent isotopes ae coelated 10

11 Atomic Yb: enegy levels and tansitions +5d6p PV amplitude: 10-9 e a 0 DeMille (1995) M μ B J.E. Stalnake, et al, PRA 66(3), (2002) β ea 0 /(V/cm) C.J. Bowes et al, PRA 59(5), 3513 (1999); J.E. Stalnake et al, PRA 73, (2006) 11

12 Stak-PV-intefeence technique (invented by the Bouchiats in 1970s)

13 The Yb PV Expeiment Electic and magnetic fields define handedness d ( )( ) Rotational Invaiant: ε B E ε B 13

14 PV effects on ates Tansition sto ates E-field modulation E E dc + R β 2 2 sin 2 0 = E θ + 2E R β cos 2 ± = E θ 2 E 1 E 0 cosωt βξ cosθ sinθ βξ cosθ sinθ intefeence m = -1 m = 0 m = +1 R +1 3 D 1 R 0 R -1 1 S 0 ( R+ 1 + R 1) R0 Compute atio = fo 1st and 2nd ham. signal st nd Ratio diffeence yields PV asymmety: ( 1 ) (2 ) = ± 2( ξ β E ) dc

15 Typical Stak-induced signal Signal Am mplitude [V] Signal Amplitude [V V] d hamonic signal fit st hamonic signal fit PNC line shape (x100) DC bias 43 V/cm Δf [MHz] 174 Yb esonance split by B 70 G; E=3 kv/cm PV asymmety: ~ / E/(kV/cm) ( ) Asymmetic lineshape AC Stak effect 15

16 Revesals and pseudo-evesals E-field evesal (14 ms: 70-Hz modulation) Lineshape scan (200 ms/point x 100 pts/lineshape = 40 s) B-field evesal (evey few minutes) Polaization angle (occasionally) E-field magnitude B-field magnitude Angle magnitude Fo θ=±π/4 16

17 Systematics contol stategy APV is mimicked by combinations of two o moe impefections Enhance one impefection; measue the othe Adapted fom the Bekeley eedm expt. of Pof. Commins et al 17

18 PV Amplitude: Results Theoetical pediction Mean value 68% confidence band (mv/cm) ζ/β Run numbe ζ/β=39(4) stat. (5) syst. mv/cm ζ =8.7± ea 0 Accuacy is affected by HV-amplifie noise, fluctuations of stay fields, and lase difts to be impoved

19 Completed Wok Pogess in Yb APV Lifetime Measuements Geneal Spectoscopy (hypefine shifts, isotope shifts) dc Stak Shift Measuements Stak-Induced Amplitude (β): 2 independent measuements M1 Measuement (Stak-M1 intefeence) ac Stak Shift Measuements Veification of APV enhancement Nea Futue Veification of expected isotopic dependence PV in odd isotopes: NSD PV, Anapole Moment PV in a sting of isotopes; neuton distibutions, Futhe Ahead (?) Testing the Standad Model [Bown et al PHYSICAL REVIEW C 79, (2009)]

20 K. Tsigutkin A. Family D. Dounas-Faze post-doc undegad gad.student V. V. Yashchuk S. J. Feedman J. E. Stalnake 20

21 Anothe atom: Dy Ideal APV amplifie? Fully degeneate opposite-paity levels Lage Z 3 (Z=66) Also Many stable isotopes: A= Lage Z 3 (Z=66) Two I=3/2 isotopes (anapole) 21

22 The paity violation expeiment in Dy evolved into 22

23 Seach fo tempoal vaiation of α in adio-fequency tansitions of Dy Suppot:

24 Seach fo tempoal vaiation of the fine-stuctue "constant" in adio-fequency tansitions of Dy 20,000 A B B A Δ 1 ) En negy (cm - 0 Gound State Δ ~ (3-2000) MHz dδ/dt ~ Hz α/α Fo α/α / ~ /y dδ/dt ~ 2 Hz/y!! Dzuba, Flambaum, Kozlov, et al

25 Result: Phys. Rev. Lett. 98, (2007) α/α = (-2.7 ± 2.6 mostly syst ) x y -1. Independent of othe fundamental constants

26 NIST Tapped-Ion/ Fequency-Comb wok

27 Population Thee-step scheme: J=9 f cm -1 τ = μs 1397 nm (b.. ~ 30%) 1st & 2nd - cw lase excitation J=10 A cm -1 τ = 7.9 μs 669 nm B J= cm -1 τ > 200 μs c J=9 e J=8 τ = 16 μs 3d - spontaneous emission J=8 G 833 nm E V E N O D D

28 f Tansition and Detection J=9 f cm -1 τ = μs f E-field excites atoms to state A J=10 A cm -1 τ = 7.9 μs f E-Field B J= cm -1 τ > 200 μs c J=9 e J=8 τ = 16 μs State A decays and 564-nm light is detected 564 nm J=8 G E V E N O D D

29 Appaatus T=1150 o C Dy atomic beam <v>=5x10 4 cm/s CW lase beams diveged fo adiabatic passage a. Oven b. Collimato c. Multi-nozzle collimato aay d. Cylindical lenses e. Lase & f inteaction egion f. Cylindical mio g. Lucite light pipe h. & i. Filtes

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31 Next steps... Succeeded in lase cooling of atomic beam Opeate new appaatus optimized fo the α-dot expeiment Measue fequency to ~1 mhz Dy APV will be back! & α α 18 ~10 /yy

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33 What we do: Fundamental symmety tests Atomic Paity Violation Yb Dy (+ lase cooling) Seach fo tempoal vaiation of alpha Testing Bose-Einstein statistics fo photons SNS Neuton EDM collaboation Schiff hff moment of Pb-207 Magnetomety Field magnetomety (Botanical Gaden) Ai- and space-bone magnetomety (with SSL, SWS, ) Measuements with mesospheic Na (with ESO) Bulk NV-diamond magnetomety Poposal: Intenational Netwok of GPS-sync mags NMR/MRI/NQR: MR imaging; NMR-capable micofluidic chips Moe atomic physics Theoy Selective addessing of high-ode polaization moments Collisional tansfe of alignment Paamagnetic atoms in cyogenic buffe gas 33

34 Supplementay Slides 34

35 New esult on Cs APV S. Posev, et al Phys. Rev. Lett. 102, (2009) In ageement with SM ( c.f. fom HEP alone) 1000-fold incease of calculation complexity Two-fold impovement in theoetical eo Result no longe theoy limited Andei Deevianko

36 PV effect on line shapes: even isotopes E = (E,0,0) 00) ε = (0,sinθ,cosθ) R E sin θ 2 E sin θ cosθ = β + β ξ β E 2 R ± = cos θ βeξsinθcosθ 2 168,170,174,176 Yb o θ PV-Stak intefeence tems 36

37 PV effect on line shapes: odd isotopes E = (E,0,0) ε = (0,sinθ,cosθ) 2 2 cente βff E 2 2 R = (4sin θ + cos θ) + βff Eξ sinθcosθ side βff E 2 R = cos θ βff Eξ sinθcosθ 2 ξ = ξ + I J ξ ξ NSD ~10-11 ea 0 fo odd Yb isotopes ξ=10-9 ea 0 ξ` must be measued with 0.1% accuacy 37 NSD

38 Optical system and contol electonics Light powes: A + : 15W Ti:Sapp (816 nm): 1 W Double (408 nm): 50 mw PBC: Confocal design, 25 cm; Finesse ~10, (upgading to 40000??) Locking: Pound-Deve-Hall technique 38