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Introduction to particle physics Part III

Physics 129, Fall 2010; Prof. D. Budker. Introduction to particle physics Part III. The amazing case of the neutral kaons. See, for example, Henley & Garcia: Subatomic Physics Prelude: the Double Well problem Parity eigenstates : Parity conservation:. With no interaction:.

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Introduction to particle physics Part III

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  1. Physics 129, Fall 2010; Prof. D. Budker Introduction to particle physicsPart III

  2. The amazing case of the neutral kaons • See, for example, Henley & Garcia: Subatomic Physics • Prelude: the Double Well problem • Parity eigenstates: • Parity conservation: With no interaction: With interaction: Symmetry: Physics 129, Fall 2010, Prof. D. Budker; http://budker.berkeley.edu/Physics129_2010/Phys129.html

  3. The amazing case of the neutral kaons • See, for example, Henley & Garcia: Subatomic Physics • Also: the Feynman Lectures, V. 3 • Perturbation theory: Physics 129, Fall 2010, Prof. D. Budker; http://budker.berkeley.edu/Physics129_2010/Phys129.html

  4. The amazing case of the neutral kaons What happens if we drop a particle in one well ? Double Well Mathematica tutorial Physics 129, Fall 2010, Prof. D. Budker; http://budker.berkeley.edu/Physics129_2010/Phys129.html

  5. The amazing case of the neutral kaons Meet the Kaons… Physics 129, Fall 2010, Prof. D. Budker; http://budker.berkeley.edu/Physics129_2010/Phys129.html

  6. The amazing case of the neutral kaons • Opposite strangeness for K and K-bar • Different particles • But both can decay to 2π • This is because weak interactions can change S Physics 129, Fall 2010, Prof. D. Budker; http://budker.berkeley.edu/Physics129_2010/Phys129.html

  7. The amazing case of the neutral kaons K-barK Physics 129, Fall 2010, Prof. D. Budker; http://budker.berkeley.edu/Physics129_2010/Phys129.html

  8. Interlude: flavor mixing by weak interactions The Cabibbo angle represents the rotation of the mass eigenstate vector space formed by the mass eigenstates into the weak eigenstate vector space formed by the weak eigenstates . θC = 13.04° Physics 129, Fall 2010, Prof. D. Budker; http://budker.berkeley.edu/Physics129_2010/Phys129.html

  9. The amazing case of the neutral kaons • Gall-Mann & Pais (1955): “double well” effects • Analog of the antisymmetricand symmetric states: • Neither C nor P respected by weak interactions, but… Physics 129, Fall 2010, Prof. D. Budker; http://budker.berkeley.edu/Physics129_2010/Phys129.html

  10. The amazing case of the neutral kaons • A K can decay into  (fast if allowed) or  (slow) • But how does a K0decay? • Say, at t=0, we make • Two-mode decay! Physics 129, Fall 2010, Prof. D. Budker; http://budker.berkeley.edu/Physics129_2010/Phys129.html

  11. The amazing case of the neutral kaons • Experimental challenge: does K0 have a long component? Physics 129, Fall 2010, Prof. D. Budker; http://budker.berkeley.edu/Physics129_2010/Phys129.html

  12. The amazing case of the neutral kaons • Strangeness oscillations • K 0 --- onlys-bar quark is present • 0 --- s quark is present again! Physics 129, Fall 2010, Prof. D. Budker; http://budker.berkeley.edu/Physics129_2010/Phys129.html

  13. The amazing case of the neutral kaons Physics 129, Fall 2010, Prof. D. Budker; http://budker.berkeley.edu/Physics129_2010/Phys129.html

  14. The amazing case of the neutral kaons • Regeneration • Light polarization analogy KS K1;KL K2 Physics 129, Fall 2010, Prof. D. Budker; http://budker.berkeley.edu/Physics129_2010/Phys129.html

  15. The amazing case of the neutral kaons • Another (incomplete) analogy: • Bi-frequency (Zel’dovich) Pendulum Physics 129, Fall 2010, Prof. D. Budker; http://budker.berkeley.edu/Physics129_2010/Phys129.html

  16. CP violation in neutral kaons Physics 129, Fall 2010, Prof. D. Budker; http://budker.berkeley.edu/Physics129_2010/Phys129.html

  17. CP violation in neutral kaons In 1963, a beam from BNL's Alternating Gradient Synchrotron and the pictured detectors salvaged from the Cosmotron were used to prove the violation of conjugation (C) and parity (P) - winning the Nobel Prize in physics for Princeton University physicists James Cronin and Val Fitch. Physics 129, Fall 2010, Prof. D. Budker; http://budker.berkeley.edu/Physics129_2010/Phys129.html

  18. CP violation in neutral kaons • Essential phenomenon: KL 2π(b.r.  2·10-3) • Was even harder to swallow that P violation • Many weird explanations; all proven wrong • Interference with regenerated Ks • More recently --- also B mesons • Direct CP violation --- penguin diagrams James Watson Cronin Val Logsdon Fitch The Nobel Prize in Physics 1980 "for the discovery of violations of fundamental symmetry principles in the decay of neutral K-mesons" Physics 129, Fall 2010, Prof. D. Budker; http://budker.berkeley.edu/Physics129_2010/Phys129.html

  19. CP violation in neutral B-mesons… Physics 129, Fall 2010, Prof. D. Budker; http://budker.berkeley.edu/Physics129_2010/Phys129.html

  20. Time reversal (T) invariance? • Arrow of time • Macroscopic (thermo-dynamical) vs. microscopic • Permanent Electric Dipole Moments: P-odd and T-odd • “Zel’dovich Moments:” • do unstable particles have EDM that do not violate T ? • Searches for EDM Physics 129, Fall 2010, Prof. D. Budker; http://budker.berkeley.edu/Physics129_2010/Phys129.html

  21. CPT and Spin-Statistics • Theorems in Quantum Field Theory • No consistent theoretical framework for violations • Need to test anyway… Physics 129, Fall 2010, Prof. D. Budker; http://budker.berkeley.edu/Physics129_2010/Phys129.html

  22. Identical particles: the ultimate equality • Individualism: the ultimate diversity • Permutation symmetry postulate • Spin-Statistics Theorem (SST)

  23. Prof. Richard P. Feynman(1918-1988) Feynman’s Lectures on Physics, V. 3:

  24. Okun’ on Pauli

  25. Doesn’t go because no symmetric statefor two photons with J=1 Landau, L. D., Dokl. Akad. Nauk., USSR 60, 207-209 (1948) How? Landau-Yang Theorem!

  26. Experimental Tests of PSPsee: Spin-Statistics Connection and Commutation Relations, AIP conference proceedings #545, R.C.Hilborn and G.M.Tino, eds., 2000 Photons  No direct tests (before present work) High energy physics:branching ratios for L-Y forbidden decays ortho-Ps, J/(1S), (2S); typ. 10-4-10-5alsoC-violating Z noC-violation, but no direct coupling21  Difficult questions: limits from lasers and static limit…

  27. The Ba 2γ experiment: Damon English

  28. S. N. Bose The degenerate two-photon transition selection rule Destructive interference of two quantum paths

  29. 1999 DeMille 1

  30. The Berkeley Experiment Animated version: YouTube: Test of Bose-Einstein statistics for photons

  31. Lasers

  32. Results

  33. Results

  34. New Force! Alec Tewsley-Booth

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