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Weak Charged Current Interactions

Weak Charged Current Interactions. charm decay. neutrino scattering. f. ~. f. ~. f.

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Weak Charged Current Interactions

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  1. Weak Charged Current Interactions charm decay neutrino scattering f ~ f ~ f As a first approximation, the weak charged current interaction couples fermions of the same generation. The Standard Model explains couplings between quark generations in terms of the Cabibbo-Kobayashi-Maskawa (CKM) matrix. Michael D Sokoloff

  2. b = f1; a = f2; g = f3 Weak Phases in the Standard Model Michael D Sokoloff

  3. BaBar Detector All subsystems crucial for CPV analysis SVT:97% efficiency, 15 mm z hit resolution (inner layers, transverse tracks) SVT+DCH: (pT)/pT = 0.13 %  pT+ 0.45 % DIRC: K- separation 4.2  @ 3.0 GeV/c  2.5  @ 4.0 GeV/c EMC:E/E = 2.3 %E-1/4  1.9 % Michael D Sokoloff

  4. e+e-  (4S)  BB m- Flavor tag and vertex reconstruction K- Btag m- Brec m+ B0 KS B0 p+ Coherent L=1 state p- Start the Clock Stop the Clock Time-Dependent CPV at the (4S) Resonance Boost: bg= 0.55 (4S) Exclusive B meson and vertex reconstruction Michael D Sokoloff

  5. } |lf| = 0.948  0.051 (stat)  0.017 (syst) Sf = 0.759  0.074 (stat)  0.032 (syst) hf =-1 sin(2b) Fit ResultsSummer 2002 hf =+1 hf =-1 sin2b = 0.755  0.074 sin2b = 0.723  0.158 sin2b = 0.741  0.067 (stat)  0.034 (sys) with |lf| = 1 Michael D Sokoloff

  6. The CKM Matrix Today Michael D Sokoloff

  7. The 2008 Nobel Prize in Physics • “The broken symmetries described by Makoto Kobayashi and Toshihide Maskawa … seem to have existed in nature since the very beginning of the universe and came as a complete surprise when they first appeared in particle experiments in 1964. It is only in recent years that scientists have come to fully confirm the explanations that Kobayashi and Maskawa made in 1972. It is for this work that they are now awarded the Nobel Prize in Physics. They explained broken symmetry within the framework of the Standard Model, but required that the Model be extended to three families of quarks. These predicted, hypothetical new quarks have recently appeared in physics experiments. As late as 2001, the two particle detectors BaBar at Stanford, USA and Belle at Tsukuba, Japan, both detected broken symmetries independently of each other. The results were exactly as Kobayashi and Maskawa had predicted almost three decades earlier.” Michael D Sokoloff

  8. 2010 Dirac Medal The 2010 Dirac Medal and Prize are awarded to Nicola Cabibbo (University La Sapienza, Rome, Italy) and Ennackal Chandy George Sudarshan (University of Texas, Austin, Texas, USA) in recognition of their fundamental contributions to the understanding of weak interactions and other aspects of theoretical physics. Cabibbo’s important contributions to theoretical physics include the recognition of the significance of mixing in weak interactions, which has established the existence of a new class of physical constants, whose first example is the Cabibbo angle. This angle determines the mixing of strange quarks with non-strange quarks and has been measured experimentally. With the discovery of a third family of quarks and leptons, quark mixing led to the understanding of the phenomenon of CP violation. Michael D Sokoloff

  9. Discovery of Narrow DSJ States (2003)[primary decay modes do not conserve isospin] Michael D Sokoloff

  10. The Y(4260): Not Anticipated, Still Not Understood Michael D Sokoloff

  11. DCS K+- D0 CF MIX D0 Charm MixingTime-Evolution of D0K Decays RS = CF WS = DCS DCS and mixing amplitudes interfere to give a “quadratic” WS decay rate (x, y << 1): where and  is the phase difference between DCS and CF decays. Michael D Sokoloff

  12. Simplified Fit Strategy & Validation Rate of WS events clearly increases with time: (stat. only) WS/RS (%) Michael D Sokoloff

  13. Simplified Fit Strategy & Validation Rate of WS events clearly increases with time: (stat. only) WS/RS (%) Inconsistent with no-mixing hypothesis: 2=24 Michael D Sokoloff

  14. Simplified Fit Strategy & Validation Rate of WS events clearly increases with time: Consistent with prediction from full likelihood fit 2=1.5 (stat. only) WS/RS (%) Inconsistent with no-mixing hypothesis: 2=24 Michael D Sokoloff

  15. Time-Dependence in D0 → KSπ+π- box size is “capped” linear box size is logarithmic Theseplots illustrate the average decay time as a function of position in the Dalitz plot for (x,y) = (0.8%, 0.3%). The sizes of the boxes reflect the number of entries, and the colors reflect the average decay time. Michael D Sokoloff

  16. Charm Mixing Today Michael D Sokoloff

  17. Discovery of the hb [2008] Michael D Sokoloff

  18. Hard scattering amplitude for qq transition which is calculable in pQCD Nonperturbative meson distribution amplitude describing the transition P  qq x: fraction of the meson momentum carried by one quark in the infinite momentum frame Michael D Sokoloff

  19. BaBar for Bean-Counters Michael D Sokoloff

  20. The Beauty of SuperB Michael D Sokoloff

  21. The Charm of SuperB 480 fb-1 75 ab-1 Michael D Sokoloff

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