CDF Experiment in JFY2002

Shin-Hong Kim (University of Tsukuba)

May 30, 2003

at KEK

Tevatron status

Luminosity goals for Run aⅡ :• 5-8x1031 cm-2sec-1 w/o Recycler• 2x1032 cm-2sec-1 with Recycler• 2 fb-1 in 2005 → 　 Run bⅡ

Achieved:• 4.6 x1031 cm-2sec-1 in May ’03• 220 pb-1 delivered until April ’03

– 170 pb-1 are on tape– 70 pb-1 analysed for 2003 w

inter conference

Schedule:• 0.3-0.4 fb-1 in total by October 2003• 2 fb-1 in Run a by the end of 2005Ⅱ• 11-15 fb-1 in Run a + Run b Ⅱ Ⅱ

Initial Luminosity

July 01

Now

Integrated Luminosity

Delivered

On tape

220 pb-1

170 pb-1

2002

2002

2001

2001

Front End ElectronicsTriggers / DAQ (pipeline)Online & Offline Software

Silicon Microstrip Tracker

Time-of-Flight

Drift Chamber

Plug Calor.

Muon

Old

New

PartiallyNew

Muon System

Solenoid

Central Calor.

Japan Group Contribution

○ Plug Calorimeter Scintillating tile/fiber unit○ Silicon Microstrip detector SVXⅡ Silicon sensor○ Inetrmediate Silicon Layer ISL 　　 Silicon sensor○ DAQ　　 Data logger, Monitor○ TOF Counter 　　 Fine-mesh photomultiplier○ RunⅡb Silicon detector SVXⅡb○ RunⅡb Central Preshower Counter CPR2

Physics Results from Run a (~70pbⅡ -1)

– W and Z boson production cross section, decay width, Wγ production cross section– Top quark production cross section and mass– Masses and lifetimes of B-hadrons – J/ψ production cross section

list

W and Z production

MT

Require two isolated energetic leptonsNegligible backgrounds

Essential for Detector CalibrationsEnergy scale and resolutionID efficiency

● Koji Ikado (Waseda) worked on the electron-ID and energy scale study.

Isolated energetic lepton and high missing ET

Need more study for missing ET calibration

W and Z production cross section: Sample Back. •B(W-->ll) (nb)

e 38625 6% 2.64±0.01stat±0.09sys±0.16lum

21599 11% 2.64±0.02stat±0.12sys±0.16lum

2346 26% 2.62±0.07stat±0.21sys±0.16lum

Sample •B(Z-->ll) (pb)

e 1830 267±6stat±15sys±16lum

1631 246±6stat±12sys±15lum

•B(W-->l) and •B(Z-->ll) at ECM=2TeV are consistent withstandard model prediction.

(pp(ppZ)Z) (W)(W) (Z (Z ee) ee)(pp(ppW)W) (W (W e e)) (Z)(Z)

RR =

TheoreticalTheoreticalpredictionprediction

PDGPDGSMSM

PDGPDGcombined combined

ExpExpMeasureMeasure

ExtractExtract

R = 10.54 R = 10.54 0.18 0.18stat stat 0.33 0.33sys sys →→ 　　　　 Γ(W) = Γ(W) = 2.15 2.15 0.04 0.04stat stat

0.070.07syssys GeVGeV

consistent with S.M. prediction of 2.09 GeVconsistent with S.M. prediction of 2.09 GeV

Background ~ 0.5%

Wγ Production

SignatureOne high pT leptonOne photon (R(-l)>0.7)High missing ET

Results consistent with SMSM: •B(W-->l) = 18.7 ±1.3 pb

Sample Back.

•B(W-->l) (pb)

e 43 33% 17.2±3.8stat±2.8sys±1.0lum

38 29% 19.8±4.5stat±2.4sys±1.2lum

●Naho Tanimoto (Okayama) performed the muon channel analysis.

Top quark pair productioncandidate event

Jet1(b-tagged)

Jet3(b-tagged)

Jet2

Jet4

Muon

Muon + Missing ET + 4Jets event(with 2b-tagged jets)

Top quark pair production cross section

Signature (W + 3 or more jets with b-tag)One high pT Isolated lepton

Veto Z, cosmic, conversionMissing ET > 20 GeV

3 or more jets with ET>15 GeV

1 jet with secondary vertex tagB tag improves S/B 1/6 3/1

Find 15 candidate events in 57.5 pb-1

Expect 3.8 ± 0.5 background events　　　　　 tt=5.3 ±1.9stat ±0.8syspb

　 Theoretical prediction = 6.5 pb

●Koji Sato (Tsukuba) studied the acceptance and the secondary vertex tag.●Soushi Tsuno (Tsukuba) worked on the study of the simulation and data comparison.

Top Quark Mass

Select l +4 jet events

Same as cross section, but no b tags33 candidate events Method

24 combinations in an event2-C fit applied, lowest 2 is chosen to get mass for each eventA continuous likelihood method is used with parameterized mass templates Mtop is the minimum of log-likelihood distribution

Systematic uncertainty will be

improved with understanding of

detector

Bs Lifetime; Bs J/φ

Use control channels: Bu J/ K+ and

Bd J/ K0*

Measurement limited only by statistics

CDF Preliminary

B+ 1.57 0.07 0.02 (ps)

Bd 1.42 0.09 0.02 (ps)

Bs 1.26 0.2 0.02 (ps)

CDF: largest fully reconstructed sample in the world: 74 11 events

Yield/Lum. = 2 x RunI

0.011.00 Prediction lTheoretica

15.089.0

)τ(B

)τ(B

d

s

First Steps towards Bs Mixing in CDF

Bs　Mixing　 Sample

Bs Ds(*) [] [[KK] ]

Collect more data and understand tagging

●Satoru Uozumi (Tsukuba) is working on the Bs mixing in Bs Ds

(*)lν channel.

Bs　Mixing　 Backup Sample

Bs Ds(*)lν [] lν [[KK] ] lν

HIGH STATISTICS SAMPLE:　 good S/N, 　　　　 limited time resolution

J/ψ Production Cross Section

(ppJ/; pT>0; ||<0.6)

=240 1 (stat) 35/28(syst) nb

In Run , CDF observed anomalous Ⅰdirect production of J/ψ and ψ(2s) in PT > 5 GeV/c which was 50 timeslarger than QCD theoretical prediction.

In Run , CDF measured the J/ψ Ⅱproduction cross section in the wholePT region, which is consitent with Run measurement.Ⅰ

●Tomohiro Yamashita (Okayama) worked on the J/ψ reconstruction and acceptance study.

Expected Physics Capability in RunⅡ

– Bs – Bs mixing ( if xs < 25, observed at 200pb-1 )

– Masses of top quark and W boson →– Direct search for Higgs particle →

Electroweak Precision Measurements

Run IIaEW Meas : MHiggs <193 GeV @95%CLLEP II Higgs Searches : MHiggs > 113 GeV @95%CLLEP II Hint @ MHiggs= 115 GeV

Tevatron Run I :Mtop = 174.3 +- 5.1 GeV/c2

MW = 80.452 +- 0.062 GeV/c2

RunⅡa: ΔMtop < 3 GeV/c2 ΔMW ～ 30 MeV/c2

→ ΔMHiggs ～ 30%

Higgs Search Capability at Tevatron(will be revised in this June)

•MH < 130 GeV/c2

pp →WHX →l +bb + X

•125 < MH < 160 GeV/c2

pp →WHX →l +W* W*+X

(like-sign dilepton +jets)

•150 GeV/c2 < MH

pp →HX →WW X →l l X

(RUN2A)

(RUN2B)

RUN2A( ～ 2005)　 exclude MH < 120 GeV/c2 at 95 ％ C.L. RUN2B(2005 ～ )　 exclude MH < 190 GeV/c2 at 95 ％ C.L　 3σ evidence for MH < 130 GeV/c2 or 155 GeV/c2 MH < 175 GeV/c2