Top quark and w boson mass at cdf
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Top Quark and W Boson Mass at CDF. Young-Kee Kim The University of Chicago Forth Workshop on Mass Origin and Supersymmetry Physics March 6-8, 2006 Tsukuba, Japan. x. x. x. x. x. x. x. x. x. x. x. Origin of Mass. There might be something (new particle?!) in the universe

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Top quark and w boson mass at cdf

Top Quark and W Boson Mass at CDF

Young-Kee Kim

The University of Chicago

Forth Workshop on Mass Origin and Supersymmetry Physics

March 6-8, 2006

Tsukuba, Japan


Origin of mass

x

x

x

x

x

x

x

x

x

x

x

Origin of Mass

There might be something (new particle?!) in the universe

that gives mass to particles.

Nothing in the universe

Something in the universe

Higgs Particles:

Coupling strength to Higgs

is proportional to mass.

Photon

Electron

Z,W Boson

Top Quark

x

x

Young-Kee Kim, Univ. of Chicago


The importance of m w and m top

The importance of MW and Mtop

Precision Electroweak Measurements

probe the Higgs bosons indirectly

by means of quantum corrections.


Quantum corrections

Quantum Corrections

  • Large quantum corrections to Electroweak observables come from the top quark.

top

top

top

bottom

W Z

Different quantum corrections to MW and MZ

With precision (better than ~1%) MW, MZ, cosW measurements,

we can predict top quark mass.

Young-Kee Kim, Univ. of Chicago


M top measurements vs prediction

Now

Mtop: Measurements vs. Prediction

Top Mass Prediction

from the global fit to EW observables

Direct measurements

from CDF and D0

Limits from direct searches

with e+e- and pp

Young-Kee Kim, Univ. of Chicago


Quantum corrections1

Inputs:

s, em(MZ2), MZ

top

bottom

80.5

80.4

80.3

W

W

200 GeV

300 GeV

Mhiggs = 100 GeV

MW (GeV)

500 GeV

1000 GeV

Higgs

150 175 200

Mtop (GeV)

  • For equal weights in 2 fits for MHiggs,

  • MW = 0.007 Mtop (Mtop = 2 GeV, MW = 14 MeV)

Quantum Corrections

  • Secondary contributions are from the Higgs.

    MW= MW0 + C1 Mtop2 + C2ln(MHiggs2)

Young-Kee Kim, Univ. of Chicago


M w m top m higgs

80.5

80.4

80.3

MW (GeV)

5 Discovery Luminosity (fb-1)

hard

hard

easy

150 175 200

100 200 300 500 800

Mtop (GeV)

MHiggs (GeV)

MW - Mtop - MHiggs

Higgs Mass:

Will the Tevatron’s prediction agree with what LHC measures?

(LP’05)

Young-Kee Kim, Univ. of Chicago


Importance of m w and m top in mssm

Importance of MW and Mtop in MSSM

Additional quantum corrections from SUSY partners

(Summer 05)

Higher precision MW and Mtop measurements will enable to distinguish

between the Standard Model, Light SUSY, and Heavy SUSY

Young-Kee Kim, Univ. of Chicago


Importance of m top in mssm

LEP2 95%CL

SM Higgs Limit

Mtop helps constraining MSSM models.

Importance of Mtop in MSSM

G. Degrassi, S.. Heinemeyer, W. Hollik, P. Slavich, G. Weiglein

Eur. Phys. Jour. C28 (2003) 133, hep-ph/0212020

Mtop

Mtop plays a key role in determining Mh in MSSM.

Young-Kee Kim, Univ. of Chicago


Top quark and w boson mass at cdf

You should go to the masseslearn from them, andsynthesize their experienceinto better, articulated principles andmethods, ….- Mao


Tevatron performance run ii

Today

LP’05

Tevatron Performance (Run II)

Peak Luminosity Int. Lum. (delivered) / Experiment

2002 2003 2004 2005

2002 2003 2004 2005

shutdown

  • Peak luminosity record: 1.8  1032 cm-2 s-1

  • Integrated luminosity

    • weekly record: 27 pb-1 / week / expt

    • total delivered: 1.5 fb-1 / expt, total recorded: 1.3 fb-1 / expt

  • Doubling time: 1 year

  • Future: ~2 fb-1 by 2006, ~4 fb-1 by 2007, ~8 fb-1 by 2009

Young-Kee Kim, Univ. of Chicago


Tevatron detectors

Tevatron Detectors

CDF

DZero

Excellent Detectors - tracking, b-tagging, calorimeter, muon

CDF Strength: momentum resolution and particle ID(K,)

DZero Strength: muon coverage and energy resolution

Young-Kee Kim, Univ. of Chicago


Tevatron m w and m top status in lepton photon 2005

Tevatron MW and Mtop Status in Lepton-Photon 2005

W Mass Top Mass

Tevatron Run I (~110 pb-1) Tevatron Run I (~110 pb-1)

+ Run II (320-350 pb-1)

Run I

Young-Kee Kim, Univ. of Chicago


W mass measurements

q

W, Z

q

g

q

e,

e,

e,

W Mass Measurements

W Z


Lepton momentum and energy scale

_

p

p

J/ +- mass vs 1/pT

p / p = - (0.10 ± 0.01)%

1 / pT(GeV-1)

CDF Preliminary

Data

MC

E(EM cal)

p / p = - (0.03 ± 0.01)%

p(tracking)

e

beampipe, silicon

e

E / p of W electrons

+- mass (GeV) near Upsilon

Lepton Momentum and Energy Scale

  • Understand passive material well:

    • Flatness of J/+-mass

      over a large pT range

    • E/p tail - data vs. simulation

  • MJ/ = 0.05 MeV

    MB = 0.2 MeV

Young-Kee Kim, Univ. of Chicago


Run ii m w status

Run II MW Status

Run II W  e

Run II W 

Data

MC

W Transverse Mass [GeV/c2] W Transverse Mass [GeV/c2]

Run II 200 pb-1 (Run Ib 90 pb-1)

Integrated Luminosity [fb-1]

MW [MeV]

CDF Run II

Young-Kee Kim, Univ. of Chicago


Top mass measurements

W+

t

t

b

q

W-

q

b

g

q

all jets: 44%

: 21%

b

q

q

e+jets:

15%

b

ee,e,: 5%

+jets: 15%

e/+jets is most powerful

Large Br, 1 - better than dilepton

Sig / Bgrnd - better than all jets

B tagging

Secondary vertex, Jet Prob., Soft e/

e+ , 

g

g

Top Mass Measurements


M top analysis method template

Mtop Analysis Method: Template

  • Select jet-parton assignment that gives the best 2

    for M(2 jets) = MW and M(top) = M(anti-top)

  • Reconstruct top mass

    • tt-bar MC “templates” with different Mtop values

    • background “templates”

    • data

  • Perform maximum likelihood fit to extract measured mass.

Young-Kee Kim, Univ. of Chicago


Mtop analysis method matrix element

Mtop Analysis Method: Matrix Element

  • Originally proposed in 1988 by Kuni Kondo

    • J. Phys. Soc. 57, 4126

  • For each event,

    • All jet-parton assignments are considered and weighted by comparing that to the leading order Matrix element calculation.

    • A probability distribution is produced.

Each curve is a probability function

from one Monte Carlo event.

Young-Kee Kim, Univ. of Chicago


Jet energy determination

Jet Energy Determination

  • Jet energy resolution

    • 84%/√ET

    • Statistical uncertainty

  • Jet energy scale

    • ~3% for jets from top decay

    • Dominant systematic uncertainty

  • New technique in Run II

    • In-situ calibration

      using W  2 jets mass

      in lepton+jets channel

Young-Kee Kim, Univ. of Chicago


M top in lepton jets template 680 pb 1

Mtop in lepton+jets: Template (680 pb-1)

Tsukuba group

(Shinhong Kim, Taka Maruyama, Tomonobu Tomura, Koji Sato)

has been playing key roles!!

Young-Kee Kim, Univ. of Chicago


M top in lepton jets and dilepton channels

Mtop in lepton+jets and dilepton Channels

Lepton+jets

Dilepton

Template Matrix Element

Mtop (template) = 173.4 ± 2.5 (stat. + jet E) ± 1.3 (syst.) GeV

Mtop (matrix element) = 174.1 ± 2.5 (stat. + jet E) ± 1.4 (syst.) GeV

Mtop (matrix element) = 164.5 ± 4.5 (stat.) ± 3.1 (jet E. + syst.) GeV

Young-Kee Kim, Univ. of Chicago


M top uncertainty run ii

Mtop Uncertainty (Run II)

CDF Run II Preliminary

CDF Combined: MtopCDF = 172.0 ± 1.6 ± 2.2 GeV = 172.0 ± 2.7 GeV

Young-Kee Kim, Univ. of Chicago


M top in l jets using decay length technique

Mtop in l+jets using Decay Length Technique

  • B hadron decay length

     b-jet boost

     Mtop

  • Difficult

    • Measure slope of exponential

  • But systematics dominated by tracking effects

    • Small correlation with traditional measurements

  • Statistics limited now

    • Can make significant contribution at LHC

Mtop (Lxy) = 183.9 +15.7-13.9 (stat.) ± 5.6 (syst.) GeV

Young-Kee Kim, Univ. of Chicago


Other cdf m top results 318 360 pb 1 data through aug 04

Other CDF Mtop results (318 - 360 pb-1 data through Aug. 04)

  • Three template-style analyses in dilepton channel

    • Combined result (340 - 360 pb-1)

      170.1 ± 6.0(stat.) ± 4.1(syst.) GeV

  • Dynamical Likelihood method (Matrix Element)

    • Lepton+jets (318 pb-1)

      173.2 +2.6-2.4(stat.) ± 3.2(syst.) GeV

      (Kohei Yorita’s Ph.D. Thesis)

    • Dilepton (340 pb-1)

      166.6 +7.3-6.7(stat.) ± 3.2(syst.) GeV

      (Ryo Tsuchiya’s Ph.D. Thesis)

63 events joint likelihood

All consistent with more recent measurements reported here.

Young-Kee Kim, Univ. of Chicago


Tevatron top mass results

Tevatron Top Mass Results

Summer 2005

New since Summer 2005

Dilepton:

CDF-II MtopME = 164.5 ± 5.5 GeV

Lepton+Jets:

CDF-II MtopTemp = 174.1 ± 2.8 GeV

CDF-II MtopME = 173.4 ± 2.9 GeV

CDF Combined:

MtopCDF = 172.0 ± 1.6 ± 2.2 GeV

= 172.0 ± 2.7 GeV

Updated CDF + DØ combined result is coming!

Young-Kee Kim, Univ. of Chicago


Electroweak projections

MW [MeV] MTop [GeV] MHiggs / Mhiggs [%]

10-1 1 10

10-2 10-1 1 10

Luminosity / Experiment [fb-1] Luminosity / Experiment [fb-1] Luminosity / Experiment [fb-1]

Electroweak Projections

CDF Run II

CDF Run II

Young-Kee Kim, Univ. of Chicago


Comments on projections e g m top

Mtop = MtopRun I / √

LumRun II / LumRun

We have been doing much better than we predicted. Data makes us smarter!

Comments on Projections (e.g. Mtop)

CDF Top Mass Uncertainties

Run I Measured

110 pb-1

Run II (2fb-1)

Projections

in 1996

Run II

Measured

318 pb-1

680 pb-1

Run II (8fb-1)

Projections

In 2005

Int. Lum [pb-1]

Young-Kee Kim, Univ. of Chicago


M w m top and m higgs in tevatron lhc ilc

MW, Mtop and Mhiggs in Tevatron/LHC/ILC

Young-Kee Kim, Univ. of Chicago


Conclusions

Conclusions

W Mass:

1st Run II meas. - coming soon (by this summer) - better than Run I

Top Mass:

MtopCDF = 172.0 ± 2.7 GeV/c2 (680 pb-1)

CDF surpassed 2 fb-1 Run II goal of 3 GeV/c2

Significant improvements in analysis techniques

Matrix element method, in situ jet energy calibration

Tevatron measurements in the LHC era:

By LHC turn-on, we expect Mtop~2 GeV, MW~30 MeV.

By the end of this decade, Mtop~1.5 GeV, MW~20 MeV

Comparable to LHC measurements

Most likely be the best for quite some time.

Higgs mass:

Will Tevatron’s prediction agree with LHC’s direct measurement?


Top quark and w boson mass at cdf

BACKUP

Young-Kee Kim, Univ. of Chicago


M w luminosity effects

MW Luminosity Effects

Effects of higher instantaneous luminosity on uncertainty

Transverse Momentum

W Transverse Mass

e,  Lepton

Transverse Momentum

Young-Kee Kim, Univ. of Chicago


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