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The Known Knowns and the Known Unknowns

The Known Knowns and the Known Unknowns. 20 Years of Tevatron Collider Physics. The Tevatron c. 2006. CDF. D0.  p. p. 1968 – Fermilab opens 1972 – Main Ring starts @ 400 GeV 1977 – CDF Department established 1982 – Tevatron begins operation @ 800 GeV 1985 – First Collisions at CDF.

marcia-stephenson
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The Known Knowns and the Known Unknowns

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  1. The Known Knowns and the Known Unknowns 20 Years of Tevatron Collider Physics

  2. The Tevatron c. 2006 CDF D0 p p • 1968 – Fermilab opens • 1972 – Main Ring starts @ 400 GeV • 1977 – CDF Department established • 1982 – Tevatron begins operation @ 800 GeV • 1985 – First Collisions at CDF Booster p p Tevatron p source Main Injector

  3. Two Hulking Detectors D0 CDF

  4. The World in 1985 u d c s Discovered at FNAL in 1977 ne e- nm m b t W, Z get their masses via the Higgs mechanism • 3 Generations of quarks and leptons t nt • Electromagnetic, Weak & Strong Forces • Electroweak & Strong Forces

  5. 3 Generations Are Needed In the SM all CP effects are related by this single phase. But for 30 years, CP was only observed in (1964 – Fitch & Cronin 1980 Nobel) 3x3 unitary matrix can be expressed with 4 parameters – 3 mixing angles + 1 complex phase Complex phase  CP Violation Particles & Antiparticles with different decay rates = CP violation

  6. 1983 • W±, Z0 discovered at CERN collider • MW~81±5 GeV/c2 • MZ=95.2±2.5 GeV/c2(UA1) • =91.9±1.9 GeV/c2(UA2)

  7. Everything is Connected Z boson PBSM?? MW Top Quark CKM MH BS Mixing B Mixing CP “When one tugs at a single thing in nature, he finds it attached to the rest of the world” – John Muir

  8. CDF December 1984

  9. September 1985 The CDF detector (not) ready to take data:

  10. First Collisions: October 13, 1985

  11. Data Taking Protons & antiprotons collide at ~2.5 MHz 0.25Hz of W/Z production ~100 Hz of high ET jets ~100 Hz of b-quark production .0002 Hz of top quark production ?? Hz of new physics 20% “Acceptance” Prescale/20 10% “Acceptance” 1% “Acceptance” 10% “Acceptance” ?? “Acceptance” ~20% Analysis Mode 85% to analysis ~1% Analysis Mode ~40% Analysis Mode ?? Analysis Mode ~10-2 Hz for analysis ~10-2 Hz for analysis ~10-5 Hz for analysis ~0.4 Hz for analysis

  12. First Precise Measurements of the Z (1989) MZ MW Phys. Rev. Lett. 63 (1989) CDF Mark II at SLC Now:

  13. W Mass MZ MW 1990: CDF used 1130 W→en & 592 W→mn to measure: 1995: 5718 W→en;3268 W→mn

  14. W Mass MZ MW MW=80.433±0.079 GeV/c2 MW=80.482±0.091 GeV/c2 14740 events 11089 events 2006: MW=XX.XXX±0.049 GeV/c2 (.06%!!!) Based on >116,000 W decays!

  15. MZ MW These two processes interfere to produce a “forward-backward” asymmetry that depends on sin2qW

  16. 1989: B0 Mixing W– • • d V*tb=1 Vtd b B0 B0 u,c,t u,c,t • • d b W+ V*tb=1 Vtd MTOP B Mixing First observation in at UA1 meant the top quark was heavy B hadron

  17. Indirect Measurements of Mtop MZ MTOP

  18. The Top Quark • In 1990 CDF published a limit • Mtop> 77 GeV/c2 This put UA1/UA2 out of business in the search for top • By 1992 the top non-discovery meant • Mtop>91 GeV/c2 • I.e. Mtop>MW+Mb

  19. What We Found: 1994 • 10 events in the lepton+jets channel (5 e, 5 m) • 2 events in the di-lepton channel (both em) • About 6 events expected from backgrounds Not your typical event

  20. The First Direct Measurement of Mtop Discovery MZ Top Mass GeV/c2 MTOP

  21. By 1995 MZ MTOP Back-to-back papers in Phys. Rev. Lett. 74 (1995) • CDF: • 37 events in lepton+jets • 6 events in dileptons • D0 • 14 events in lepton+jets • 3 events in dileptons

  22. 2006 MZ MW MTOP MH Mtop= 171.4 ± 2.1 GeV/c2

  23. Mtop, MW & MHiggs MW MTOP MH Soon

  24. Higgs

  25. W Polarization in Top Decay b SM says V-A t W+

  26. Single Top Top Quark CKM W* Vtb here A very tough measurement

  27. B Physics b

  28. CKM 1989 Assuming 3 generation unitarity

  29. CP Violation in B mesons CKM B Mixing CP A triangle in the complex plane (provided the CKM phase is non-zero) Unitarity of CKM matrix  (among other things)

  30. First Hint b≠0 (1999) CKM B Mixing CP Now, from b factories: Unfortunately, the SM is quite happy with this.

  31. BS Oscillations V*tb=1 Vts W– • • s b Bs Bs u,c,t u,c,t • • s b W+ V*tb=1 Vts CKM BS Mixing Mixing Frequency is  |Vts|2

  32. Matter-Antimatter Oscillations CKM BS Mixing 2.8THz ms = 17.33 +0.42 (stat) ± 0.07 (syst) ps-1

  33. CKM 2006 CKM BS Mixing Still assumes 3 generation unitarity. BS Mixing measurement

  34. Rare Decays PBSM? CKM V*tb=1 W+ • • m+ b Bs t n • • s m- W- Vts Corrections from BSM physics can enhance this significantly and g-2 of the muon as well. CDF+D0 limit BR<1.5x10-7

  35. Supersymmetry PBSM?? Add this complication. Get this simplification.

  36. PBSM??

  37. Interesting Events Happen1995: PBSM?? Missing Energy (GeV) That’s interesting…

  38. The EggMet Event PBSM?? Two high-energy electrons Two high-energy photons Large missing energy ?? Nothing more through 2006…

  39. Everything is Connected Z boson PBSM?? MW Top Quark CKM MH BS Mixing B Mixing CP “When one tugs at a single thing in nature, he finds it attached to the rest of the world” – John Muir

  40. You’re going to be told lots of things. You get told things every day that don’t happen. It doesn’t seem to bother people, they don’t – It’s printed in the press. The world thinks all these things happen. They never happened. Everyone’s so eager to get the story Before in fact the story’s there That the world is constantly being fed Things that haven’t happened. All I can tell you is, It hasn’t happened. It’s going to happen.

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