Ph T eV - radcor2000.slac.stanford.edu

Electroweak Physics at the TeVatron

Kevin McFarland

University of Rochester

RADCOR-2000

Carmel-by-the-Sea, California

11 September 2000

Kevin McFarland, RADCOR-2000, Electroweak Physics at the TeVatron 2

NuTeV

CDF D0

Main

TeVatron

Injector

1. Introduction, Goals, Musings

2. On-Shell Physics

� W Properties

� Multi-Boson Final States

3. O�-Shell Physics

� NuTeV sin2 �W

� Drell-Yan4. Discovering a Higgs

5. Conclusions


Status of TeVatron

Where’s CDF?

Cosmicin COT,

Calorimeter


Status of TeVatron (cont'd)

� TeVatron has achieved

pp collisions

with Main Injector

.ps = 1960 GeV

. L � 1027, c.f. design

L of 2� 1032

� CDF being installed for (short) \commissioning" run

� CDF/D0 to be ready for beam by March 1, 2001

. \or else"

� Initial running with 36 bunch operation in machine

. Occupancy a concern

0.1

1.0

10.0

100.0

Average Number ofInteractions per Crossing

1E+

30

1E+

31

1E+

32

1E+

33

Luminosity

10 3 0

10 3 1

10 3 2

10 3 3

6 Bunches

36 Bunches

108 Bunches

designlum.

. Hope for quick transition to 99 bunch operation,

Æt = 132 ns


Status of Precision Electroweak

Measurements:

A Three Hour Tour?

A dozen years ago. . .

� The basic structure of the electroweak Standard Modelappeared correct

. Low-energy measurements of � Z interference and Z ex-

change

. Crude boson masses

� Time was ripe for a quick BIG SURPRISE

. Fat Z?

. Generation dependence in couplings?

. Physics at TeV mass scales appearing in precision measure-

ments?

. Other

�Who ordered this?

. Certainly not an experimentalist!



Measurements (cont'd)

Measurement Pull Pull-3 -2 -1 0 1 2 3

-3 -2 -1 0 1 2 3

mZ [GeV]mZ [GeV] 91.1875 ± 0.0021 .05

ΓZ [GeV]ΓZ [GeV] 2.4952 ± 0.0023 -.42

σhadr [nb]σ0 41.540 ± 0.037 1.62

RlRl 20.767 ± 0.025 1.07

AfbA0,l 0.01714 ± 0.00095 .75

AeAe 0.1498 ± 0.0048 .38

AτAτ 0.1439 ± 0.0042 -.97

sin2θeffsin2θlept 0.2321 ± 0.0010 .70

mW [GeV]mW [GeV] 80.427 ± 0.046 .55

RbRb 0.21653 ± 0.00069 1.09

RcRc 0.1709 ± 0.0034 -.40

AfbA0,b 0.0990 ± 0.0020 -2.38

AfbA0,c 0.0689 ± 0.0035 -1.51

AbAb 0.922 ± 0.023 -.55

AcAc 0.631 ± 0.026 -1.43

sin2θeffsin2θlept 0.23098 ± 0.00026 -1.61

sin2θWsin2θW 0.2255 ± 0.0021 1.20

mW [GeV]mW [GeV] 80.452 ± 0.062 .81

mt [GeV]mt [GeV] 174.3 ± 5.1 -.01

∆αhad(mZ)∆α(5) 0.02804 ± 0.00065 -.29

Osaka 2000

(Figure courtesy of LEP EWWG)



Measurements (cont'd)

0

2

4

6

10 102

103

mH [GeV]

∆χ2

Excluded Preliminary

∆αhad =∆α(5)

0.02804±0.00065

0.02755±0.00046

theory uncertainty

(Figure courtesy of LEP EWWG)


Struggling to Find New Physics

Where, if anywhere in the precision data, are there

indications for deviations from Standard Model

expectations in the precision data that would guide us as

we begin to search again at the TeVatron?

� sin2 �e�; leptonsW

vs sin2 �e�; quarksW

� Also �0had

10 2

10 3

0.23 0.232 0.234

Preliminary

sin2θlept

eff

mH [

GeV

]

χ2/d.o.f.: 5.7 / 5

χ2/d.o.f.: 11.9 / 6

Afb0,l 0.23099 ± 0.00053

Aτ 0.23192 ± 0.00053Ae 0.23117 ± 0.00061Afb

0,b 0.23225 ± 0.00036Afb

0,c 0.23262 ± 0.00082<Qfb> 0.2321 ± 0.0010

Average(LEP) 0.23184 ± 0.00023

Al(SLD) 0.23098 ± 0.00026

Average(LEP+SLD) 0.23146 ± 0.00017

∆αhad= 0.02804 ± 0.00065∆α(5)

αs= 0.119 ± 0.002mt= 174.3 ± 5.1 GeV

� Atomic Parity

Violation (137Cs)


Atomic Parity Violation

� Z Interference

e

e

Z,γ

� Interaction suppressed by q2=M 2Z

� But not in forbidden (6S $ 7S) transitions (parity-violating)

� Magnitude of interference (parity-violating) relative to -exchange

gives

hQW i = hQEMi (light quarks)

Recent 137Cs APV measurement

Bennett,S.C. and Wieman,C.E. PRL 82, 2482-2487 (1999)

QW = �72:06� 0:28(exp)� 0:34(theory)

QSMW = �73:09� 0:03

\I believe our sigmas mean a bit more than the

sigmas that you use [in particle physics]."

Carl Wieman, at an FNAL Seminar


On-Shell or O�-Shell?

� LEP Z pole data disfavors most new physics in the

weak neutral current itself

� However, this constraint still

allows for new physics in o�-

shell processes

� New interactions can't strongly

a�ect Z pole

� E.g., Z 0 exchange, unmixed

Z’

Z’

Z’Z

Z

q

l

l

q

l

q

Pure Z’ exchange

Z-Z’ Mixing

� Global �t shows some Z-Z 0 mixing allowed

. � 10�3 weakly favored?Langacker and Erler, PRL 84, 212-215 (2000)


On-Shell (W Properties)

p_

p

W,Z, γ

l

l, ν

� W production is dominant source of

high pt leptons at TeVatron

�(pp! W )� BR(W ! `�)

�(pp! Z)� BR(Z ! ``)� 10

� Drell-Yan extends

to very high

mass `+`� pairs

� Generally clean,

\obvious" sample0

200

400

600

800

1000

1200

25 30 35 40 45 50 55pT(e) (GeV)

num

ber

of e

vent

s

candidatesW e νD0


W Mass

� �, GF , MZ ) MW at tree level

� MW measurement probes radiative corrections

W W

t

b

W W

h0

W∆MW α MT

2 ∆MW α ln MH

W W

?

?New Physics

. Constraint on Higgs mass

. Key consistency check for model

80.1

80.2

80.3

80.4

80.5

80.6

130 140 150 160 170 180 190 200Mtop (GeV/c2)

MW

(G

eV/c

2 )

100

250

500

1000

Higgs Mass (

GeV/c2 )

TEVATRON

MW-Mtop contours : 68% CL

LEP2

LEP1,SLD,νN dataMW-Mtop contours : 68% CL

80.1

80.2

80.3

80.4

80.5

80.6

130 140 150 160 170 180 190 200

�Mtop= 5:1 GeV, �MW

= 63 MeV


W Mass (cont'd)

CDF/D0 Technique:

� Infer neutrino transverse

kinematics from~p�T = � ~uT � ~p`T

uT

lepton

ν

� Form mT =r2p`Tp

�T (1� cos(�` � ��))

� Select events with high p`T (25 or 30 GeV)and low uT (below 15 or 20 GeV)

. CDF,D0: central,��`

�� < 1

. D0: endcap e, 1:5 <��`

�� < 2:5 (� 30% of sample)

. � 4� 104 events per experiment

� Fit mT to extract mW

(D0 �ts p`t and p�t as well)

0

500

1000

1500

2000

50 60 70 80 90 100 110 120

CDF(1B) PreliminaryW→eν

χ2/df = 82.6/70 (50 < MT < 120)

χ2/df = 32.4/35 (65 < MT < 100)

Mw = 80.473 +/- 0.065 (stat) GeV

KS(prob) = 16%

Fit region

Backgrounds

Transverse Mass (GeV)

# E

vent

s

0

50

100

150

200

250

300

350

400

450

500

50 60 70 80 90 100 110 120

CDF(1B) PreliminaryW→µν

χ2/df = 147/131 (50 < MT < 120)

χ2/df = 60.6/70 (65 < MT < 100)

Mw = 80.465 +/- 0.100 (stat) GeV

KS(prob) = 21%

Fit region

Backgrounds

Transverse Mass (GeV)

# E

vent

s


W Mass (cont'd)

Systematics: p`t measurement

� Primary control from Z ! `+`� data

0

50

100

150

200

250

70 80 90 100 110

CDF(1B) Preliminary

Z→ee χ2/df=1.3

0

50

100

150

200

250

80 90 100

CDF(1B) Preliminary

Z→µµ χ2/df=0.89

-0.01

-0.005

0

0.005

0.01

30 40 50 60

CDF(1B) Preliminary

ET (GeV) : W+Z events

E/p

Res

idua

ls:D

AT

A-M

C

W Z

∆Mw = 34 +/- 17 MeV

� Attempt to cross-check this with E=p determination in

CDF 1B electron data failed by 4�, (�MZ � 500MeV)

� Highlights diÆculty of measurement

� ÆMW � 70{85 MeV (Run I)

Systematics: Recoil Model

� Response of detectors to underlying event

� Measured (again) in Z ! `+`� data



W Mass (cont'd)

Systematics: d�=dy

� Direct e�ect on lineshape in �t

Well constrained from W charge asymmetry

-0.2

-0.15

-0.1

-0.05

0

0.05

0.1

0.15

0.2

0.25

0 0.25 0.5 0.75 1 1.25 1.5 1.75 2 2.25 2.5

d/u : Variation for Mw analysis

MRS-TMRS-T(MOD)

MRS-R1(MOD)MRS-R1

MRS-R2MRS-R2(MOD)

Lepton Rapidity

Cha

rge

Asy

mm

etry


Systematics: Scaling for Run II

� Most systematics now directly constrained from W;Z

data ) statistically limited

0

50

100

150

200

250

300

350

400

450

500

0 0.1 0.2 0.3 0.4 0.5 0.6

� Anticipate �MWof 20{40 MeV

from �rst 2fb�1 (early 2003?) from CDF/D0

� Control of theoretical systematics also key { see talk by D. Wackeroth


W Width

� TeVatron high statistics W sample ideal for study of

W properties

� Run II (2 fb�1 per experiment),

expect 106 W

� W lineshape as a measure of

�W

� High mT dominated by Breit-

Wigner, not resolution MT(e,ν) (GeV)

Transverse mass lineshape(normalized to unit area)for ΓW=1.5,1.7,...,2.5 GeV

CDF Preliminary

10-5

10-4

10-3

10-2

10-1

40 60 80 100 120 140 160 180 200

MT(e,ν) (GeV)

even

ts /

GeV CDF(1B) Preliminary

ΓW = 2.175 ± 0.165 GeV(stat+syst)

MT(e,ν) (GeV)

even

ts /

2GeV 49844 events shown

(1490 ± 170 bkg)438 with 100<MT<200 GeV211 with 110<MT<200 GeV

7 with MT>200 GeV

0

1000

2000

40 60 80 100 120 140 160 180 200

1

10

10 2

10 3

40 60 80 100 120 140 160 180 200

-2 log(L) vs ΓW

325

330

335

340

345

350

355

360

1.6 1.8 2 2.2 2.4 2.6 2.8

MT(µ,ν) (GeV)

# E

vent

s

CDF(1B) PreliminaryΓW = 1.78 +- 0.240 GeV

ΤW

-2 lo

g(L

)

MT(µ,ν) (GeV)

# E

vent

s

Backgrounds

196 ev. in fit region(100 < MT < 200)

21791 ev. in normalisation region(50 < MT < 200)

0

250

500

750

1000

50 100 150 200

246

248

250

252

1 1.5 2 2.5 3

10-1

1

10

10 2

10 3

50 100 150 200

CDF

�W = 2:055� 0:100� 0:075

0

0.1

0.2

0.3

0.4

0.5

0.6

0.7

0.8

0.9

1

1.5 1.6 1.7 1.8 1.9 2 2.1 2.2 2.3 2.4 2.51.5 2.0 2.5ΓW[GeV]

ALEPH 2.17±0.20

DELPHI 2.09±0.15

L3 2.19±0.21

OPAL 2.04±0.18

LEP 2.12±0.11

LEP Preliminary : Summer 2000

-CDF 2.06+0.12

Run II (2 fb�1),

��W � 20{40 MeV


W/Z Production

� W , Z boson production also is a clean way to

probe proton constituents

p_

x2

pl

l, νW,Z

x1

� MV =px1x2s

� Role in precision measurements

. e.g., W mass and W asymmetry

-0.2

-0.15

-0.1

-0.05

0

0.05

0.1

0.15

0.2

0.25

0 0.25 0.5 0.75 1 1.25 1.5 1.75 2 2.25 2.5

d/u : Variation for Mw analysis

MRS-TMRS-T(MOD)

MRS-R1(MOD)MRS-R1

MRS-R2MRS-R2(MOD)

Lepton Rapidity

Cha

rge

Asy

mm

etry


W/Z Production (cont'd)

0

10

20

30

40

50

60

70

80

0 0.5 1 1.5 2 2.5 3y

dσ(γ* /Z

)/d

y (

pb

)

CDF 1992-95 e+e-

χ2/ndofLO(CTEQ5L), 33.3/27NLO(MRST99), 23.1/27NLO(CTEQ5M-1), 24.3/27

x2

x1

x1=MZeys-1/2

x2=MZe-ys-1/2

66< Mγ*/Z < 116 GeV/c2

(a)

0.031 0.019 0.011 0.007 0.004

0.05 0.084 0.138 0.227 0.374 0.617 1.0

Forward e� reconstruction key for these measurements

Silicon tracking and EM calorimetry only!

0

0.05

0.1

0.15

0.2

0.25

0.3

0.35

0.4

0.45

-3 -2 -1 0 1 2 3

CC,CP,CF,PP,PF CC,CP,CF CC

y

εAr

COT

0

.5

1.0

1.5

2.0

0 .5 1.0 1.5 2.0 2.5 3.0

END WALLHADRONCAL.

SVX II5 LAYERS

30

3 00

SOLENOID

INTERMEDIATE SILICON LAYERS

CDF Tracking Volume

= 1.0

= 2.0

EN

D P

LUG

EM

CA

LOR

IME

TER

EN

D P

LUG

HA

DR

ON

CA

LOR

IME

TER

= 3.0

n

n

n

m

m


Gauge Boson Couplings

� Standard Model allows for non-zero trilinear

Gauge boson couplings

. WW , WWZ allowed

. ZZ , Z , ZZZ zero at tree level

� Search for non-Standard couplings to probe structure

of physics beyond Standard Model

� Multi-boson signatures clean if W;Z ! leptons

. again, waiting increased LCAL+TKS END VIEW 15-MAY-1997 13:27 Run 89912 Event 23020 26-MAR-1995 22:54

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MUON

ELEC

TAUS

VEES

OTHER

EM

ICD+MG

HAD

MISS ET

Max ET = 51.6 GeV MISS ET(3)= 40.8 GeV ETA(MIN:-25-MAX: 25)

EM2

EM3

EM1

Miss. Et

MT(2)=74.7 GeV M13=93.6 GeV

Run I D0 WZ candidate!


Gauge Boson Couplings (cont'd)

ALEPH 0.09 +0.18−0.14

DELPHI 0.25 +0.21−0.17

L3 −0.12 +0.16−0.14

OPAL 0.00 +0.27−0.19

LEP 0.06 +0.09−0.09

D0 −0.05 +0.30−0.30

LEP+D0 0.05 +0.09−0.08

preliminary

χ2/Ndof = 2.08/4

∆κγ

-∆ln

L

0

1

2

3

-0.5 0 0.5

ALEPH −0.05 +0.07−0.06

DELPHI 0.02 +0.08−0.08

L3 0.00 +0.07−0.07

OPAL −0.11 +0.08−0.07

LEP −0.03 +0.04−0.04

D0 0.00 +0.10−0.10

LEP+D0 −0.03 +0.03−0.03

preliminary

χ2/Ndof = 1.48/4

λγ

-∆ln

L

0

1

2

3

-0.2 -0.1 0 0.1 0.2

� Expect scaling withpL (or better)

� WZ signature unique to hadron colliders


O�-Shell: NuTeV

ACCEPTEDπ,Κ

DUMPEDπ,Κ

Right-SignDUMPEDNuTeV

SSQT Sign TrainQuadrupoleSelected

��

Wrong-Sign

Protons

�NC

�CC

+sin2 ��NW

Event Length

ν

q q

W

µ

Event Length

q

ν

q

Z

ν

Short (NC) Events Long (CC) Events R20 � Short=Long

� 386K 919K 0:4198� 0:0008(stat)

� 88.7K 210K 0:4215� 0:0017(stat)


PRELIMINARY NuTeV sin2�W

NuTeV measures:

sin2�W

(on�shell)=

0:2253� 0:0019(stat)� 0:0010(syst)

sin2 �(on�shell)W � 1� MW

2

MZ2

� The most precise �N measure-

ment of the weak mixing angle

� Precision comparable to collider

measurements ...

79.9 80.1 80.3 80.5 80.7 80.9Mw (GeV)

UA2

CDF*

D0*

NuTeV*

ALEPH*

DELPHI*

L3*

OPAL*

World Average

* : Preliminary

80.26 +/- 0.110

80.360 +/- 0.370

80.433 +/- 0.079

80.482 +/- 0.091

80.449 +/- 0.065

80.308 +/- 0.091

80.353 +/- 0.088

80.446 +/- 0.064

80.419 +/- 0.038


NuTeV sin2�W (cont'd)

R�=

��NC � ��NC��CC � ��CC

=

0B@1

2� sin2 �W

1CA

= u2L + d2L � u2R � d2R

NuTeV measurement! constraint on the Z0-quark couplings:

0:4530� sin2 �W =

0:2277� 0:0022 =

0:8587u2L + 0:8828d2L � 1:1657u2R � 1:2288d2R

g2L;R = u2L;R + d2L;R

0.02

0.03

0.04

0.29 0.3 0.31

SM

NuTeV R�constraint:

�0:0068� 0:006 =

+ 1:6134�uL + 0:9972�uR� 2:0631�dL � 0:5261�dR

APV constraint:

(QexpW �QSM

W )=QSMW =

0:014� 0:006 =

+ 5:1436(�uL +�uR)

+ 5:7729(�dL + �dR)� 2�geA


Extra Z Bosons?

� Several authors have suggested E(6) Z 0 as the mostnatural interpretation of APV data

. Rosner, Casalbuoni et al, unmixed Z 0

. Erler and Langacker, general case

� APV, NuTeV (and pp Drell-Yan) all sensitive to direct

Z 0 exchange (interference)

95% Con�dence Level Lower Mass Limits on Z0

':

Z0

= Z�cos� + Z sin�

NuTeV Limits (mixing=-10�3) Rosner hep-ph/9907524

mZ� � 675 GeV at 95% CL Casalbuoni, et al. hep-ph/0001215

mZ� � 380 GeV at 95% CL


High Mass Drell-Yan

� Search for highest

mass `�`�

� Sensitive to

``qq contact inter-

actions, Z 0

D0 Run I

e+e� sample

� Sample is clean, fertile ground for new physics

Comparison of the data with the SM predictions

10-2

10-1

1

10

10 2

10 3

0 100 200 300 400 500 600

M(EM-EM), GeV

Eve

nts

M(EM-EM), GeVM(EM-EM), GeVM(EM-EM), GeV

DØ (2000)Run I, 127 pb-1

Dielectrons and diphotons

ET(EM) > 45 GeV

|η| < 1.1 or 1.5 < |η| < 2.5

SM

Instrumental background

Limits on Large Spatial Extra Dimensions

0.2

0.3

0.4

0.5

0.6

0.7

0.8

0.4 0.6 0.8 1 1.2 1.4 1.6 1.8 2MS , TeV

F/M

S ,4 T

eV −

4

n = 2, MS > 1.37 TeVn = 3, MS > 1.44 TeV

n = 4, MS > 1.21 TeVn = 5, MS > 1.10 TeV

n = 6, MS > 1.02 TeV

n = 7, MS > 0.97 TeV

95% CL UpperLimit on F/MS

4

F = 2/(n-2), n > 2

F = 2log( ), n = 2

(after Han et al.

PRD 59 (1999) 1050060)

MS

0.6 TeV

DØ (2000)


High Mass Drell-Yan (cont'd)

p_

p

W,Z, γ

l

l, ν

� O�-shell, forward-backward asymmetry is large

-0.2

-0.1

0

0.1

0.2

0.3

0.4

0.5

0.6

60 80 100 120 140 160 180 200

� Assume Standard Model behavior on Z pole;

probe high-mass region and therefore interference

� CDF new result in process;

enhanced angular coverage using forward events!


High Mass Drell-Yan (cont'd)

� Forward e� de�ned by EM calorimeter. . .

� . . . in conjunction with silicon stub

. charge determination!

y

φcal

pTmax

pTmin

rcal

� Probing o�-shell (interference) key for Z 0 searches!

(Rosner, Phys. Rev. D54 1078)

� �=Z�=Z 0� interference is sig-

nature of Z 0

� Di�erentiates among E(6) Z 0

possibilities

� Just awaiting L:::


90 130

σ(pp_→H+X) [pb]

√s = 2 TeV

Mt = 175 GeV

CTEQ4Mgg→H

qq→Hqqqq

_’→HW

qq_→HZ

gg,qq_→Htt

_

gg,qq_→Hbb

_

MH [GeV]

10-4

10-3

10-2

10-1

1

10

10 2

80 100 120 140 160 180 200

Standard Model Higgs

� Discovery of the Higgs would complete the experimen-

tal veri�cation of the electroweak Standard Model

� SM Higgs:

. Single doublet of scalar �elds

. Predicts couplings but not Higgs mass

Decay

� For 90 < MH < 130GeV,

BR(H ! b�b) varies between

0.85 and 0.60.

� At MH > 140 GeV,

H ! WW � dominates

Production at TeVatron

� V H production provides

additional handle for

background rejection.

� �(WH)=�(ZH) � 1:6

� gg ! H, H ! bb

hopeless at TeVatron


CDF Run I Searches

No signal observed !

WH ! `� b�b V H ! qqb�bExpect : 30� 5 1-tag, 6:0� 0:6 2-tag Expect : 600 2-tag events

Observe : 36 1-tag, 6 2-tag Observe : 589 2-tag events

0

1

2

0 50 100 150 200 250 300

Entries 5

Data (5 events)

Total background (3.2 events)

Dijet Mass (GeV)

Eve

nts

/ (10

GeV

)

ZZ + tt + mistags only

ZH ! `+`� b�b ZH ! ��b�bExpect : 3:2� 0:7 1-tag Expect : 39:2� 4:4 1-tag, 3:9� 0:6 2-tag

Observe : 5 Observe : 40 1-tag, 4 2-tag


1

10

10 2

70 80 90 100 110 120 130 140

Higgs Mass (GeV/c2)

σβ (

pb)

σ(pp− → VH0)β CDF 95% C.L.

CDF PRELIMINARY

VH0 → qq− bb

−

VH0 → lν− bb

−

combined (lν−, qq

−)

VH0 → νν− bb

−

combined :VH0 → l+l- / νν

− bb

−

standard model

CDF Run I Searches (cont'd)

� Limits � 50� SM expectations with 0:1 fb�1

� 2 fb�1 is still not enough


Run II Prospects

0

2

4

6

10 102

103

mH [GeV]

∆χ2

Excluded Preliminary

∆αhad =∆α(5)

0.02804±0.00065

0.02755±0.00046

theory uncertainty

� Precision data stronglysuggest that Higgs is

below 190 GeV

� Suggests opportunity

at TeVatron with high

luminosity

� Two mass ranges:

. MH < 130 GeV

H ! bb

. MH > 130 GeV

H ! WW �

MH < 130 GeV MH > 130 GeV

V H V H and gg

`�bb, ��bb, `+`�bb `+`+jj, `+`+`�, `+`�

-20

-10

0

10

20

30

40

50

0 20 40 60 80 100 120 140 160 180 200

Dijet Invariant Mass (GeV/c2)

Eve

nts

per

10 G

eV/c

2

Excess over background— Expected MC shape (PYTHIA)

Predicted bgr.

Observed events

Dijet Mass (GeV/c2)

Eve

nts

per

10 G

eV/c

2

0

20

40

60

80

100

0 50 100 150 200

Low backgrounds make

analysis viable, even with

low cross-sections and low

branching ratios into lep-

tons


Run II Prospects

Run 2B

Run 2

(Run II Higgs Working Group, All V H Channels and

gg ! H;H ! WW � )

� With 2 fb�1 can probe MH up to � 115GeV/c2.

� Need � 20 fb�1 for a 3� signal for MH to 180 GeV

� Prospects for luminosity beyond 15 fb�1 before LHC

are unclear


Conclusions

The TeVatron is Poised

for a Long Run!

� \The Signature" for Run II is W/Z ! `(�=`)

. 106 W by 2003!

. Precision measurements: W mass and width

. Using W as a tool: parton distributions,

luminosity calibration for TeVatron

. Multi-boson production

� \The targets" for New Physics in Run II (2 fb�1)

. Z 0 (testing Wieman's \sigma" calibration)

. Weak couplings of top (Willenbrock's talk)

� Standard Model Higgs

. Requires 10{20 fb�1 to get in the game

. TeVatron is a tough place to study a

114:9 GeV Higgs (just to pick a random number)

. Good news: broad range of masses accessible!

. More good news: H ! WW � clean

Documents

Ph T eV - radcor2000.slac.stanford.edu