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A.RuizBEACH2000 CP Violation and B-mixing in CDF-II IV International Conference on Hyperons, Charm and Beauty Hadrons June, 27-30, 2000 Valencia,Spain Alberto Ruiz Jimeno Instituto de Física de Cantabria (CSIC-Univ. Cantabria) Santander,Spain
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A.RuizBEACH2000 CP-Violation and B-mixing in CDF-II Outline Short summary of results on CP Violation and B-Mixing from Run-I Detector Upgrade Flavor tagging Prospective for CP Violation and B-mixing in Run-II Conclusions
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A.RuizBEACH2000 CP-Violation and B-mixing in CDF-II 1992-1995 : 110 pb -1 collected B d mixing B s mixing
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A.RuizBEACH2000 CP-Violation and B-mixing in CDF-II Golden mode for CP-violation analysis: B0 J/ K s (measure of sin 2 ) Total signal: 395 31 events Sin 2 = 0.79 +0.41 -0.44
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A.RuizBEACH2000 CP-Violation and B-mixing in CDF-II Fermilab Main Injector: 150 GeV accelerator 1/2 Radius of Tevatron: 20 times luminosity ( starting 8-20 x 10 31 cm -2 seg -1 ) 2 fb -1 in two years 15 fb -1 up to 2006 Proton/antiproton bunch spacing: 132 nsec ( 108 bunches) 396 nsec (36 bunches) Overlapping interactions ( 2-6 on average)
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A.RuizBEACH2000 CP-Violation and B-mixing in CDF-II Tracking: SVX-II ( 5 layers, double side. 2.4-10.7 cm. 60 pitch. 12 resolution. | ISL ( 2 layers, double side. 20 -28 cm. 110 -146 pitch. 16 resolution | COT (Open cell drift chamber. Drift time < 132 nsec. 44-132 cm. 96 layers, 8 superlayers, 4 r 4 z 180 resolution. | dE/dx information Muon systems, double coverage. | New scintillating tile plug calorimeter 1<|
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A.RuizBEACH2000 CP-Violation and B-mixing in CDF-II Beyond Baseline: Layer 00 ( rad-hard single-sided silicon layer. 1.6 cm. 50 pitch) T.O.F. 216 bars Bicron BC408. 4x4 cm. 2.8 m.long Hamamatsu PMT´s 19 stages fine-mesh 100 psec. Resolution (see S.Cabrera talk)
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A.RuizBEACH2000 CP-Violation and B-mixing in CDF-II 2 K/ separation for p<1.6 GeV/c TOF and dE/dx complementary
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A.RuizBEACH2000 CP-Violation and B-mixing in CDF-II Trigger: Level 1 : 50 Khz. Muons (CMU stubs, p t >3 GeV/c) Electrons ( 4 GeV single tower) XFT: extremely fast tracks: | p t | > 1.5 GeV/c | z | < 155 cm. Between inner and outer COT radius Performance: (p t )/ p t 2 = 0.012 (GeV/c) R = 106 cm )< 0.0015 rad XTRP: tracks distribution
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A.RuizBEACH2000 CP-Violation and B-mixing in CDF-II Trigger: Level 2 : 300 Hz. (many asynchronous subsystems) (e.g.): Two-tracks ( e.g. B All hadronic B- trigger Soft lepton + XFT track (using SVT) SVT trigger: information from XFT and silicon vertex detector Level 3 : 30 Hz. ( Farm of computers)
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A.RuizBEACH2000 CP-Violation and B-mixing in CDF-II 120 < |d 0 |< 1 mm. Lepton + displaced track trigger
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A.RuizBEACH2000 CP-Violation and B-mixing in CDF-II Signal sizes for some channels, before tagging, for 2 fb -1 : ( S/B studied for each channel, using Run I data, when possible)
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A.RuizBEACH2000 CP-Violation and B-mixing in CDF-II Flavor tagging methods : To determine the flavor at production time Opposite side Tags (OST) : Soft lepton tag (SLT) Opposite side Kaon tag Jet charge (JTEQ) Same side tag (SST) Kaon tags need TOF -> K -
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A.RuizBEACH2000 CP-Violation and B-mixing in CDF-II Pythia MC reproduces SST in data TOF enhances D K veto SST OST Kaon
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A.RuizBEACH2000 CP-Violation and B-mixing in CDF-II Tagging Efficiency x (Dilution Factor) 2 ( D 2 )
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A.RuizBEACH2000 CP-Violation and B-mixing in CDF-II 01 Unitarity triangle = arg ( -V td V ub V * tb V * ud ) = arg ( -V cd V tb V * cb V * td ) = arg ( -V ud V cb V * ub V * cd ) Wolfenstein parametrization...
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A.RuizBEACH2000 CP-Violation and B-mixing in CDF-II btq W W MIXING
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A.RuizBEACH2000 CP-Violation and B-mixing in CDF-II Without L00, 60 fs With L00, 45 fs B s oscillations True versus meas. Asym. S/B = 1/2 Potential of B s mixing observation
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A.RuizBEACH2000 CP-Violation and B-mixing in CDF-II B s mixing in semileptonic decays B s D s l D s * l D s Trigger: lepton + SVT track (p t >2 GeV/c, d 0 >120 ) t corrected by K factor X s reach: reach of Hadronic B s decays including 3d vertex correction without 3d vertex correction
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A.RuizBEACH2000 CP-Violation and B-mixing in CDF-II CP violation: Channel J/ K s A CP (t) requires flavor tagging at production, signal reconstruction and decay time Scaling RunI analysis (including TOF) 10 K events, (sin(2 )) = 0.067 New triggers, 30Kevents, (sin(2 )) = 0.043
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A.RuizBEACH2000 CP-Violation and B-mixing in CDF-II If only one weak phase, If more than one weak phase ( case of penguin pollution, as in B d ),
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A.RuizBEACH2000 CP-Violation and B-mixing in CDF-II Measuring from: better than 10º with 2 fb -1 (Penguin/tree)
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A.RuizBEACH2000 CP-Violation and B-mixing in CDF-II Measuring from: A toy MC 2, 5, 10, 20 fb -1
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A.RuizBEACH2000 CP-Violation and B-mixing in CDF-II Measuring with: (If is a strong phase) Use as f, the double Cabibbo suppresed decays K - as well as f Unknowns b in the four equations from d and d *
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A.RuizBEACH2000 CP-Violation and B-mixing in CDF-II Defining the asymmetry Expected signal rate in 2 fb -1, is in the order of 100 events after trigger selection. Background estimation is on study
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A.RuizBEACH2000 CP-Violation and B-mixing in CDF-II Measuring from: K+K+ K-K- p.d.f. ( CP even decays): 3/8 ( 1 + cos 2 p.d.f. ( CP odd decays): 3/4( sin 2 Heavy and light weak eigenstates are in a close approximation the CP even and odd states. The distribution of the decay products allows for a separation of the CP eigenstates In Run II more than 4000 events expected. will be measured with a value of 0.15 and a precision of about 0.051, if the CP even fraction is 0.771. Using other channels ( B s D + s D s - ) precision will be better Toy MC results
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A.RuizBEACH2000 CP-Violation and B-mixing in CDF-II CONCLUSIONS CDF will start data taking in March 2001 The prospects for B-physics are very good, from the start
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A.RuizBEACH2000 CP-Violation and B-mixing in CDF-II More information: S.Bailey, P.Maksimovic: CDF/ANAL/BOTTOM/CDFR/4863 A.Cerri,G.Punzi,G.Signorelli: CDF/ANAL/BOTTOM/PUBLIC/4881 M.Paulini: CDF/PUB/BOTTOM/PUBLIC/5200 A. Cerri: CDF/DOC/BOTTOM/CDFR/5243 F.Würthwein: CDF/ANAL/BOTTOM/CDFR/5271 C.Blocker: CDF/BOTTOM/PHYS/PUBLIC/5289 M.Tanaka: CDF/ANAL/BOTTOM/CDFR/5290 W.Wester: CDF/ANAL/BOTTOM/CDFR/5298 F.Azfar, L.Lyons, M.Martin, C.Pauss, J.Tseng: CDF/ANAL/BOTTOM/CDFR/5300 M.Kirk, J.Lewis, M.Tanaka: CDF/DOC/TRIGGER/CDFR/5324 B.Wicklund: Contribution to the RUN II B-Workshop, Fermilab M.Jones: Contribution to the RUN II B-Workshop, Fermilab J.Kroll: Contribution to the RUN II B-Workshop, Fermilab ……..Many thanks to all of them
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