The Known Knowns and the Known Unknowns 20 Years of Tevatron Collider Physics
p pp CDFD0 Main Injector Tevatron Booster pp p p source The Tevatron c 1968 – Fermilab opens 1972 – Main Ring 400 GeV 1977 – CDF Department established 1982 – Tevatron begins 800 GeV 1985 – First Collisions at CDF
Two Hulking Detectors CDF D0
The World in Generations of quarks and leptons t e e - udud cscs b Discovered at FNAL in 1977 Electromagnetic, Weak & Strong Forces Electroweak & Strong Forces W, Z get their masses via the Higgs mechanism
3 Generations Are Needed Particles & Antiparticles with different decay rates = CP violation 3x3 unitary matrix can be expressed with 4 parameters – 3 mixing angles + 1 complex phase Complex phase CP Violation 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)
1983 W ±, Z 0 discovered at CERN collider –M W ~81±5 GeV/c 2 –M Z =95.2±2.5 GeV/c 2 (UA1) – =91.9±1.9 GeV/c 2 (UA2)
B S Mixing Everything is Connected “When one tugs at a single thing in nature, he finds it attached to the rest of the world” – John Muir Z bosonTop Quark MWMW MHMH B Mixing CP CKM PBSM??
CDF December 1984
September 1985 The CDF detector (not) ready to take data:
First Collisions: October 13, 1985
Data Taking Protons & antiprotons collide at ~2.5 MHz 0.25Hz of W/Z production ~100 Hz of high E T jets ~100 Hz of b-quark production.0002 Hz of top quark production ?? Hz of new physics 1% “Acceptance” ~1% Analysis Mode ~10 -2 Hz for analysis 10% “Acceptance” ~40% Analysis Mode ~10 -5 Hz for analysis ?? “Acceptance” ?? Analysis Mode 20% “Acceptance” ~20% Analysis Mode ~10 -2 Hz for analysis Prescale/20 10% “Acceptance” 85% to analysis ~0.4 Hz for analysis
First Precise Measurements of the Z (1989) CDF Mark II at SLC Now: Phys. Rev. Lett. 63 (1989) MZMZ MWMW
W Mass 1990: CDF used 1130 W→e & 592 W→ to measure: 1995: 5718 W→e ; 3268 W→ MZMZ MWMW
W Mass M W =80.433±0.079 GeV/c events M W =80.482±0.091 GeV/c events 2006: M W =XX.XXX±0.049 GeV/c2 (.06%!!!) Based on >116,000 W decays! MZMZ MWMW
MZMZ MWMW These two processes interfere to produce a “forward- backward” asymmetry that depends on sin 2 W
1989: B 0 Mixing b W–W– d bd W+W+ u,c,t B0B0 B0B0 V td V* tb =1 First observation in at UA1 meant the top quark was heavy B hadron M TOP B Mixing
Indirect Measurements of M top MZMZ M TOP
The Top Quark In 1990 CDF published a limit –M top > 77 GeV/c 2 This put UA1/UA2 out of business in the search for top By 1992 the top non-discovery meant –M top >91 GeV/c 2 –I.e. M top >M W +M b
What We Found: events in the lepton+jets channel (5 e, 5 ) 2 events in the di- lepton channel (both e ) About 6 events expected from backgrounds Not your typical event
The First Direct Measurement of M top MZMZ M TOP Discovery Top Mass GeV/c 2
By 1995 CDF: –37 events in lepton+jets –6 events in dileptons D0 –14 events in lepton+jets –3 events in dileptons Back-to-back papers in Phys. Rev. Lett. 74 (1995) MZMZ M TOP
2006 M top = ± 2.1 GeV/c 2 MZMZ M TOP MWMW MHMH
M top, M W & M Higgs Soon M TOP MWMW MHMH
Higgs
W Polarization in Top Decay t b W+W+ SM says V-A
Single Top W*W* V tb here A very tough measurement Top Quark CKM
B Physics b
CKM 1989 Assuming 3 generation unitarity
CP Violation in B mesons Unitarity of CKM matrix (among other things) A triangle in the complex plane (provided the CKM phase is non-zero) CP CKM B Mixing
First Hint ≠0 (1999) Now, from b factories: Unfortunately, the SM is quite happy with this. CP CKM B Mixing
B S Oscillations b W–W– s bs W+W+ u,c,t BsBs BsBs V ts V* tb =1 Mixing Frequency is |V ts | 2 CKM B S Mixing
Matter-Antimatter Oscillations 2.8THz m s = (stat) ± 0.07 (syst) ps-1 CKM B S Mixing
CKM 2006 Still assumes 3 generation unitarity. B S Mixing measurement CKM B S Mixing
Rare Decays b W+W+ s W-W- t BsBs V ts V* tb =1 Corrections from BSM physics can enhance this significantly and g-2 of the muon as well. CDF+D0 limit BR<1.5x10 -7 CKM PBSM?
Supersymmetry Add this complication. Get this simplification. PBSM??
Interesting Events Happen 1995: Missing Energy (GeV) That’s interesting… PBSM??
The EggMet Event Two high-energy electrons Two high-energy photons Large missing energy Nothing more through 2006… PBSM??
B S Mixing Everything is Connected “When one tugs at a single thing in nature, he finds it attached to the rest of the world” – John Muir Z bosonTop Quark MWMW MHMH B Mixing CP CKM PBSM??
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.