1. Physics 129, Fall 2010; Prof. D. Budker

2. Physics 129, Fall 2010, Prof. D. Budker; http://budker.berkeley.edu/Physics129_2010/Phys129.html 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:

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

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

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

6. Physics 129, Fall 2010, Prof. D. Budker; http://budker.berkeley.edu/Physics129_2010/Phys129.html 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

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

8. Physics 129, Fall 2010, Prof. D. Budker; http://budker.berkeley.edu/Physics129_2010/Phys129.html 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. θ C = 13.04°

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

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

11. Physics 129, Fall 2010, Prof. D. Budker; http://budker.berkeley.edu/Physics129_2010/Phys129.html The amazing case of the neutral kaons Experimental challenge: does K 0 have a long component?

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

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

14. Physics 129, Fall 2010, Prof. D. Budker; http://budker.berkeley.edu/Physics129_2010/Phys129.html The amazing case of the neutral kaons Regeneration Light polarization analogy K S  K 1 ; K L  K 2

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

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

17. Physics 129, Fall 2010, Prof. D. Budker; http://budker.berkeley.edu/Physics129_2010/Phys129.html 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.

18. Physics 129, Fall 2010, Prof. D. Budker; http://budker.berkeley.edu/Physics129_2010/Phys129.html CP violation in neutral kaons Essential phenomenon: K L  2π (b.r.  2·10 -3 ) Was even harder to swallow that P violation Many weird explanations; all proven wrong Interference with regenerated K s 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"

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

20. Physics 129, Fall 2010, Prof. D. Budker; http://budker.berkeley.edu/Physics129_2010/Phys129.html 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 EDMSearches for EDM

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

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

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

24. Okun’ on Pauli

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

26. Experimental Tests of PSP see: Spin-Statistics Connection and Commutation Relations, AIP conference proceedings #545, R.C.Hilborn and G.M.Tino, eds., 2000  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 -5 also C-violating Z   no C-violation, but no direct coupling   2  1  Difficult questions: limits from lasers and static limit… Photons

27. The Ba 2γ experiment: Damon English

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

29. DeMille 1 1999

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

31. Lasers

32. Results

34. New Force! Alec Tewsley-Booth