cdf experiment in jfy2002 shin-hong kim (university of tsukuba) may 30, 2003 at kek
TRANSCRIPT
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