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

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The Known Knowns and The Known Knowns and the Known Unknownsthe Known Unknowns

20 Years of Tevatron Collider Physics

p p CDF D0

Main Injector

TevatronBooster

p source

The Tevatron c. 2006

1968 – Fermilab opens

1972 – Main Ring starts @ 400 GeV

1977 – CDF Department established

1982 – Tevatron begins operation @ 800 GeV

1985 – First Collisions at CDF

Two Hulking Detectors

The World in 1985

• 3 Generations of quarks and leptons

Discovered at FNAL in 1977

• Electromagnetic, Weak & Strong Forces• Electroweak & Strong Forces

0, , ,W Z g

W, Z get their masses via the Higgs mechanism

3 Generations Are Needed

c ud us ub

c cd cs cb

c td ts tb

d V V V d

s V V V s

b V V V b

Particles & Antiparticles with different decay rates = CP violation d s ds

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)

0 0K K

• 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)

BS 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 boson

Top Quark

B Mixing CP

PBSM??

CDF December 1984

September 1985

The CDF detector (not) ready to take data:

First Collisions: October 13, 1985

Data Takingp p 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

1% “Acceptance”

~1% Analysis Mode

~10-2 Hz for analysis

10% “Acceptance”

~40% Analysis Mode

?? “Acceptance”

?? Analysis Mode

20% “Acceptance”

~20% Analysis Mode

Prescale/20 10%

“Acceptance”

85% to analysis

~0.4 Hz for analysis

First Precise Measurements of the Z (1989)

291.11 0.23GeV/cZM 290.9 0.36 GeV/cZM

CDFMark II at SLC

291.1876 0.0021 GeV cZM Now:

Phys. Rev. Lett. 63 (1989)0Z e

W Mass

1990: CDF used 1130 W→e & 592 W→ to measure:

279.91 0.39WM GeV c

1995: 5718 W→e ; 3268 W→ 280.410 0.180WM GeV c

W MassMW=80.433±0.079 GeV/c2

14740 events

MW=80.482±0.091 GeV/c2

11089 events

2006: MW=XX.XXX±0.049 GeV/c2 (.06%!!!)

Based on >116,000 W decays!MZ

2 2 2sin 1W W ZM M

These two processes interfere to produce a “forward-backward” asymmetry that depends on sin2W

1989: B0 Mixing

u,c,tu,c,tB0 B0

•Vtd

V*tb=1

First observation in at UA1 meant the top quark was heavy

b bB hadron 0B

B Mixing

Indirect Measurements of Mtop

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

What We Found: 1994

• 10 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 Mtop

2174 16 GeV ctopM

Discovery Top Mass GeV/c2

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)

2176 13 GeV ctopM MZ

Mtop= 171.4 ± 2.1 GeV/c2

Mtop, MW & MHiggs

ln HMSoon

W Polarization in Top Decay

SM says V-A2

Longitudinal Left LongitudinalW top

MF F F

Single Top

Vtb here

A very tough measurement

Top Quark

B Physics

CKM 1989

ud us ub

cd cs cb

td ts tb

0.9747 0.9759 0.218 0.224 0.001 0.007

0.218 0.224 0.9734 0.9752 0.030 0.058

0.003 0.019 0.029 0.058 0.9983 0.9996

Assuming 3 generation unitarity

CP Violation in B mesonsUnitarity of CKM matrix (among other things)

* * * 0ub ud cb cd tb tdV V V V V V A triangle in the complex plane (provided the CKM phase is non-zero)

*ud ubV V *

td tbV V

*cd cbV V

sin 2S SN B J K N B J K

B Mixing

First Hint ≠0 (1999)

0.410.44sin 2 0.79

Now, from b factories: sin 2 0.687 0.032

Unfortunately, the SM is quite happy with this.

B Mixing

BS Oscillations

u,c,tu,c,tBs Bs

•Vts

V*tb=1

Mixing Frequency is |Vts|2

BS Mixing

Matter-Antimatter Oscillations

2.8THz

ms = 17.33 +0.42 (stat) ± 0.07 (syst) ps-1

BS Mixing

CKM 2006

ud us ub

cd cs cb

td ts tb

0.97377 0.00027 0.2257 0.0021 4.31 0.30 10

0.230 0.011 0.957 0.095 41.6 0.6 10

7.4 0.8 10 40.6 2.7 10 0.9982 0.0002

Still assumes 3 generation unitarity.

BS Mixing measurement

BS Mixing

Rare Decays

tBs•

V*tb=1

9~ 10sBR B

Corrections from BSM physics can enhance this significantly and g-2 of the muon as well.

CDF+D0 limit BR<1.5x10-7CKM

Supersymmetry

Add this complication. Get this simplification.

PBSM??

Interesting Events Happen1995:

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??

BS 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 boson

Top Quark

B Mixing CP

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.

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

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