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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
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4th Workshop on Mass Origin & Supersymmetry: Mar 6-8, 2006, TsukubaYoung-Kee Kim, Univ. of Chicago 2 Nothing in the universe Something in the universe Higgs Particles: Coupling strength to Higgs is proportional to mass. x x x xx x x xx x xx x Photon Electron Z,W Boson Top Quark There might be something (new particle?!) in the universe that gives mass to particles. Origin of Mass
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The importance of M W and M top Precision Electroweak Measurements probe the Higgs bosons indirectly by means of quantum corrections.
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4th Workshop on Mass Origin & Supersymmetry: Mar 6-8, 2006, TsukubaYoung-Kee Kim, Univ. of Chicago 4 Quantum Corrections Large quantum corrections to Electroweak observables come from the top quark. Different quantum corrections to M W and M Z top bottom W Z With precision (better than ~1%) M W, M Z, cos W measurements, we can predict top quark mass.
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4th Workshop on Mass Origin & Supersymmetry: Mar 6-8, 2006, TsukubaYoung-Kee Kim, Univ. of Chicago 5 M top : Measurements vs. Prediction Now Top Mass Prediction from the global fit to EW observables Limits from direct searches with e+e- and pp Direct measurements from CDF and D0
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4th Workshop on Mass Origin & Supersymmetry: Mar 6-8, 2006, TsukubaYoung-Kee Kim, Univ. of Chicago 6 Quantum Corrections WWWW top bottom Higgs Secondary contributions are from the Higgs. M W = M W 0 + C 1 M top 2 + C 2 ln(M Higgs 2 ) M top (GeV) M W (GeV) 150 175 200 80.5 80.4 80.3 M higgs = 100 GeV 200 GeV 300 GeV 500 GeV 1000 GeV Inputs: s, em (M Z 2 ), M Z For equal weights in 2 fits for M Higgs, M W = 0.007 M top ( M top = 2 GeV, M W = 14 MeV)
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4th Workshop on Mass Origin & Supersymmetry: Mar 6-8, 2006, TsukubaYoung-Kee Kim, Univ. of Chicago 7 M W - M top - M Higgs M top (GeV) M W (GeV) 150 175 200 80.5 80.4 80.3 Higgs Mass: Will the Tevatron’s prediction agree with what LHC measures? M Higgs (GeV) 5 Discovery Luminosity (fb -1 ) hard easy 100 200 300 500 800 (LP’05)
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4th Workshop on Mass Origin & Supersymmetry: Mar 6-8, 2006, TsukubaYoung-Kee Kim, Univ. of Chicago 8 Importance of M W and M top in MSSM Additional quantum corrections from SUSY partners (Summer 05) Higher precision M W and M top measurements will enable to distinguish between the Standard Model, Light SUSY, and Heavy SUSY
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4th Workshop on Mass Origin & Supersymmetry: Mar 6-8, 2006, TsukubaYoung-Kee Kim, Univ. of Chicago 9 Importance of M top in MSSM M top G. Degrassi, S.. Heinemeyer, W. Hollik, P. Slavich, G. Weiglein Eur. Phys. Jour. C28 (2003) 133, hep-ph/0212020 M top plays a key role in determining M h in MSSM. LEP2 95%CL SM Higgs Limit M top helps constraining MSSM models.
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You should go to the masses learn from them, and synthesize their experience into better, articulated principles and methods, …. - Mao
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4th Workshop on Mass Origin & Supersymmetry: Mar 6-8, 2006, TsukubaYoung-Kee Kim, Univ. of Chicago 11 Tevatron Performance (Run II) Peak luminosity record: 1.8 10 32 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 2002 2003 2004 2005 Peak Luminosity Int. Lum. (delivered) / Experiment shutdown LP’05 Today
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4th Workshop on Mass Origin & Supersymmetry: Mar 6-8, 2006, TsukubaYoung-Kee Kim, Univ. of Chicago 12 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
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4th Workshop on Mass Origin & Supersymmetry: Mar 6-8, 2006, TsukubaYoung-Kee Kim, Univ. of Chicago 13 Tevatron M W and M top Status in Lepton-Photon 2005 Run I W Mass Top Mass Tevatron Run I (~110 pb -1 ) + Run II (320-350 pb -1 )
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W Mass Measurements q q g W, Z q e, e, W Z
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4th Workshop on Mass Origin & Supersymmetry: Mar 6-8, 2006, TsukubaYoung-Kee Kim, Univ. of Chicago 15 Lepton Momentum and Energy Scale Understand passive material well: Flatness of J/ + - mass over a large p T range E/p tail - data vs. simulation M J/ = 0.05 MeV M B = 0.2 MeV p / p = - (0.03 ± 0.01)% + - mass (GeV) near Upsilon p / p = - (0.10 ± 0.01)% pppp _ 1 / p T (GeV -1 ) J/ + - mass vs 1/p T E / p of W electrons Data MC p(tracking) E(EM cal) beampipe, silicon e e CDF Preliminary
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4th Workshop on Mass Origin & Supersymmetry: Mar 6-8, 2006, TsukubaYoung-Kee Kim, Univ. of Chicago 16 Run II M W Status Run II W e Run II W Uncert.Source e II (Ib) II(Ib) Statistics45 (65)50(100) e/ p Scale 70 (80)30 (87) Recoil Energy50 (37)50 (35) Backgrounds20 (5)20 (25) Prod. & Decay 30 (30) Total105(110)85(140) Run II 200 pb -1 (Run Ib 90 pb -1 )Integrated Luminosity [fb -1 ] M W [MeV] CDF Run II W Transverse Mass [GeV/c 2 ] Data MC
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Top Mass Measurements q q g tttt q W+W+ b b W-W- g all jets: 44% e+jets: 15% +jets: 15% : 21% ee,e , : 5% 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/ b b q q e +, g
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4th Workshop on Mass Origin & Supersymmetry: Mar 6-8, 2006, TsukubaYoung-Kee Kim, Univ. of Chicago 18 M top Analysis Method: Template Select jet-parton assignment that gives the best 2 for M(2 jets) = M W and M(top) = M(anti-top) Reconstruct top mass –tt-bar MC “templates” with different M top values –background “templates” –data Perform maximum likelihood fit to extract measured mass.
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4th Workshop on Mass Origin & Supersymmetry: Mar 6-8, 2006, TsukubaYoung-Kee Kim, Univ. of Chicago 19 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.
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4th Workshop on Mass Origin & Supersymmetry: Mar 6-8, 2006, TsukubaYoung-Kee Kim, Univ. of Chicago 20 Jet Energy Determination Jet energy resolution –84%/√E T –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
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4th Workshop on Mass Origin & Supersymmetry: Mar 6-8, 2006, TsukubaYoung-Kee Kim, Univ. of Chicago 21 M top in lepton+jets: Template (680 pb -1 ) Tsukuba group (Shinhong Kim, Taka Maruyama, Tomonobu Tomura, Koji Sato) has been playing key roles!!
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4th Workshop on Mass Origin & Supersymmetry: Mar 6-8, 2006, TsukubaYoung-Kee Kim, Univ. of Chicago 22 M top in lepton+jets and dilepton Channels M top (template) = 173.4 ± 2.5 (stat. + jet E) ± 1.3 (syst.) GeV M top (matrix element) = 174.1 ± 2.5 (stat. + jet E) ± 1.4 (syst.) GeV Template Matrix Element M top (matrix element) = 164.5 ± 4.5 (stat.) ± 3.1 (jet E. + syst.) GeV Lepton+jets Dilepton
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4th Workshop on Mass Origin & Supersymmetry: Mar 6-8, 2006, TsukubaYoung-Kee Kim, Univ. of Chicago 23 M top Uncertainty (Run II) Source of Uncertainty lepton+jets Template (680 pb -1 ) lepton+jets Matrix Element (680 pb -1 ) dilepton Matrix Element (750 pb -1 ) Statistics / Jet Energy Scale2.5 4.5 / 2.6 Residual / Bgrnd Jet E Scale0.80.42 Monte Carlo Statistics0.30.04 Monte Carlo Generators0.20.190.5 Initial State Gluon Radiation0.50.720.5 Final State Gluon Radiation0.20.760.5 Parton Distribution Functions0.30.120.6 b-tagging0.10.31 b jet Energy Scale0.60.60 Background Modeling0.50.211.1 Total2.82.95.5 CDF Run II Preliminary CDF Combined: M top CDF = 172.0 ± 1.6 ± 2.2 GeV = 172.0 ± 2.7 GeV
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4th Workshop on Mass Origin & Supersymmetry: Mar 6-8, 2006, TsukubaYoung-Kee Kim, Univ. of Chicago 24 M top in l+jets using Decay Length Technique B hadron decay length b-jet boost M top 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 M top (L xy ) = 183.9 +15.7 -13.9 (stat.) ± 5.6 (syst.) GeV
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4th Workshop on Mass Origin & Supersymmetry: Mar 6-8, 2006, TsukubaYoung-Kee Kim, Univ. of Chicago 25 Other CDF M top 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.
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4th Workshop on Mass Origin & Supersymmetry: Mar 6-8, 2006, TsukubaYoung-Kee Kim, Univ. of Chicago 26 Tevatron Top Mass Results Summer 2005 Dilepton: CDF-II M top ME = 164.5 ± 5.5 GeV Lepton+Jets: CDF-II M top Temp = 174.1 ± 2.8 GeV CDF-II M top ME = 173.4 ± 2.9 GeV CDF Combined: M top CDF = 172.0 ± 1.6 ± 2.2 GeV = 172.0 ± 2.7 GeV New since Summer 2005 Updated CDF + DØ combined result is coming!
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4th Workshop on Mass Origin & Supersymmetry: Mar 6-8, 2006, TsukubaYoung-Kee Kim, Univ. of Chicago 27 Electroweak Projections M W [MeV] M Top [GeV] M Higgs / M higgs [%] Luminosity / Experiment [fb -1 ] Luminosity / Experiment [fb -1 ] Luminosity / Experiment [fb -1 ] 10 -1 1 10 10 -2 10 -1 1 10 CDF Run II
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4th Workshop on Mass Origin & Supersymmetry: Mar 6-8, 2006, TsukubaYoung-Kee Kim, Univ. of Chicago 28 Comments on Projections (e.g. M top ) Run I Measured 110 pb -1 Run II (2fb -1 ) Projections in 1996 318 pb -1 680 pb -1 Run II Measured CDF Top Mass Uncertainties Run II (8fb -1 ) Projections In 2005 M top = M top Run I / √ Lum Run II / Lum Run Int. Lum [pb -1 ] We have been doing much better than we predicted. Data makes us smarter!
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4th Workshop on Mass Origin & Supersymmetry: Mar 6-8, 2006, TsukubaYoung-Kee Kim, Univ. of Chicago 29 M W, M top and M higgs in Tevatron/LHC/ILC
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Conclusions W Mass: 1st Run II meas. - coming soon (by this summer) - better than Run I Top Mass: M top CDF = 172.0 ± 2.7 GeV/c 2 (680 pb -1 ) CDF surpassed 2 fb -1 Run II goal of 3 GeV/c 2 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 M top ~2 GeV, M W ~30 MeV. By the end of this decade, M top ~1.5 GeV, M W ~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?
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4th Workshop on Mass Origin & Supersymmetry: Mar 6-8, 2006, TsukubaYoung-Kee Kim, Univ. of Chicago 31 BACKUP
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4th Workshop on Mass Origin & Supersymmetry: Mar 6-8, 2006, TsukubaYoung-Kee Kim, Univ. of Chicago 32 M W Luminosity Effects Effects of higher instantaneous luminosity on uncertainty W Transverse Mass e, Lepton Transverse Momentum Transverse Momentum
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