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The weak interaction studied in traps

The weak interaction studied in traps. introduction to the weak interaction -decay from inclusive to exclusive measurements the weak charge parity non-conserving (PNC) transitions the electric dipole moment time reversal violation (TRV) the importance of traps. Hans Wilschut

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The weak interaction studied in traps

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  1. The weak interaction studied in traps • introduction to the weak interaction • -decay • from inclusive to exclusive measurements • the weak charge • parity non-conserving (PNC) transitions • the electric dipole moment • time reversal violation (TRV) • the importance of traps Hans Wilschut KVI –Groningen (NL)

  2. neutral charged e e- e e- Z0 W± e e- e e- Leptons and weak bosonslow energy interactions The leptons: (e-, e) ; (e+, e) (-, ) ; (+, ) (-, ) ; (+, ) The bosons: W+,W-,Z0 Now ! : e  e - e-  W± Z0 e-   e-

  3. p Putting in the quarkslow energy interactions APAC: only light quarks The quarks: (u, d) (s, c) (t, b) Vud Vus p  n q-change dud e e d(-1/3) n W± W± e- u(+2/3) e- uud generation change PNC e s(-1/3) e- n W± Z0 n e- u(+2/3) e-

  4. (N,Z) (N-1,Z+1) W± e- -decay charged currents Initial and final state of nucleus let you steer the detail of decay Fermi transitions 0+ 0+  + N N’ e,  + Gamow-Teller 1+ 0+ “The Nucleus as micro laboratory” Decay probability  (phase space) (nuclear structure) (weak interact)

  5. Structure of the weak interaction Of all possible interactions only few are allowed characterization by the Dirac matrices involved Structure is V - A= left handed interaction “beyond” = right handedness new bosons more Higgs’s or….. = S, P or T Scalar Pseudo Scalar Vector (GV) Axial Vector (GA) Tensor

  6. Inclusive observable1: decay rate Decay probability  (phase space) (nuclear structure) (weak interact) super-allowed fermi decay: ignore nuclear structure (almost) integrate phase space  Q5 • Vud = 0.9740  0.0005 • i|Vui|2 = 0.9968  0.0014 New candidates 62Ga,66As,70Br,74Rb need accurate Q…..Penning trap! Z of daugther

  7. Exclusive measurements integrate over all spin variables only a and b remain

  8. Measurement strategies exclusive electron-neutrino correlation electron-recoil correlation inclusive electron distribution recoil distribution recoil direct: TRAPS indirect: recoil messenger How does it work?

  9. Inclusive observables2: Recoil distribution Impact of - on recoil Fermi Gamow-Teller Recoil e  e Recoil  Vector Scalar

  10. Best measurement for aF Adelberger et al. PRL83(99)1299 32Ar  32Cl + e+ +  ; 32Cl  31S + p aF=0.9989(52)(39) 107 cts S V exp line shape Higher order corrections folded in: not measured Direct measurement for 6He aGT= 0.3343(30) New measurements U. Leuven @ ISOLDE

  11. Correlation experiments Setup at TRIUMF (Behr et al.) for 38mK (t1/2=0.93 s; 0+  0+)

  12. Current value aF=0.992(8)(5) improved statistics ? (3)(3) current limitation:  response other attempts: aGT 6He at LPC/GANIL with Paul trap

  13. Correlation experiments: spin degrees of freedom  <J> vs  : “A = Wu experiment” Vieira et al. (LANL) 82Rb (t1/2=75 s; 1+ 0+, (2+) ) (SM: A 1) Behr et al. 37K (t1/2=1.23 s; 3/2+ 3/2+, (5/2+)) (SM: A structure dependent) add recoil measurement: TRV (D) TRIP Na: LBL(Freedman) Li: Japan

  14. The weak interaction neutral currents (N,Z) (N,Z) ,Z0 e- e- However,… Vem Qe + spin + …. VPV  QW + anapole + ….

  15. How to measure PNC? It is too weak to measure directly: mix with normal transition Make AWlarge AWZ3 and A emsmall (not too small) Cs experiments 6S1/27S1/2 Use Stark effect for A em Best result from Boulder experiment QW= 72.1  0.3  0.9 theory= 73.20  0.13

  16. How to measure PNC? It is to weak to measure directly: mix with normal transition F=4 F=4 F=4 7S1/2 7S1/2 7S1/2 F=3 F=3 F=3 6P3/2 6P3/2 6P3/2 F=4 F=4 F=4 6S1/2 6S1/2 6S1/2 F=3 F=3 F=3

  17. “The Bouchiats’ program” for the future • Other experiments in reliable atoms • radioactive Fr program at Stony Brook • and started at Legnaro • single Ba+ Paul trap (laser cooled) Seattle • Spin dependent PNC • anapole (133Cs done) • Isotope dependence • QW=  N there are more radioactive • isotopes than stable ones • Other • molecules: enatiomers

  18. Time reversal violation and EDM TRV is possible in the SM__ CP or T violation in K0 K0 Vdx d u,c,t s __ K0 K0 W W _ _ _ _ _ s u,c,t d immeasurably small otherwise extensions SM have much larger EDM EDM tool for theory selection

  19. Washington Seattle de < 8.7 10-28 e cm

  20. EDM activities Any object will do: consider method  guidance by theory • point particles e,, • nucleons n • nuclei Tl, Hg “new ideas” Storage rings (APAC99) Ra+,Ra (atomic, nuclear enhancements)

  21. Fundamental Interactions Nuclear physics Atomic physics Applied physics Summary and outlook -decay condensates Nuclear structure - and -decay Atomic moments Electric dipole Atomic structure chemistry Nuclear moments very rare isotope detection NIPNET HITRAP BETANET Gascatcher EXOTRAP EUROTRAP

  22. Why traps? Maximal experimental control TRIP

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