or the keys to open the door of the BSM world Aurore Savoy-Navarro, LPNHE, Université Pierre et Marie Curie/CNRS-IN2P3, Paris, France HADRON COLLIDER PHYSICS HADRON COLLIDER PHYSICS Summer school 2008 Summer school 2008 FNAL WINE & CHEESE seminar FNAL WINE & CHEESE seminar FERMILAB, August 15, 2008 FERMILAB, August 15, 2008 Wine&Cheese, Aug15 2008 1
Let’s try some of these BSM Keys(*): This talk tries to give just some ideas on the capabilities and present achievements of CDF experiment to confront the BSM, which is the main goal ahead of us. • HEAVY FLAVOUR : How precision measurements may lead to BSM, the Bs sector & some flavour of rare B decays • EWK : W mass, double & forbidden boson couplings • TOP : mass and some non standard top properties. • HIGGS sector: the many ways to look for a light Higgs • Breaking the waves : Some BSM “typical” signatures: multijets and multileptons. But first of all THE KEY -ISSUE= to build the needed detector ⇒ the main assets of the constantly rejuvenated CDF detector http://www-cdf.fnal.gov/physics/S08CDFResults.html Wine&Cheese, Aug15 2008 2
Tevatron is breaking records is breaking records Tevatron (and it better does: LHC first collisions Sept 10 th ) As of today about 4.6 fb-1 delivered, 4 fb-1 recorded 3.16 x 10 32 cm -2 s -1 Currently: 50 pb - -1 1 /week /week Currently: 50 pb Wine&Cheese, Aug15 2008 3
Competition coming… Courtesy Lyn Evans At last! GOOOOOOOOOOOOD!!! GOOOOOOOOOOOOD!!! Wine&Cheese, Aug15 2008 4
It’s not enough to have a high luminosity machine; you must be able to cope with it in the best (im) possible way Wine&Cheese, Aug15 2008 5
L00 + µvertex ISL: intermediate Si tracker Si vertex trigger: SVT Since over about 3 decades (!!), several generations of experimentalists have been working on building and continuously upgrading CDF with innovative and pioneering ideas making it to be still today at the forefront and able to make discoveries (top, Bs mixing and more still to come) plus important breakthroughs both in Physics and Detector techniques. Central Outer gaseous Part of the Muon detector Plug calorimeter Tracker (COT) Wine&Cheese, Aug15 2008 6
Very important contribution of Tracker in CDF Trigger Architecture XFT – Level 1 7.6 MHz Crossing rate Upgrade: all trck pT>1.5 GeV 3D tracks XFT here σ (1/pT) = 1.7%/GeV L1 L1 L1 σ ( φ 0) = 5 mrad pipeline • 7.6 MHz Synchromous 96% efficiency 42 clock Pipeline cycles • 5.5 µ s Latency SVT – Level 2 Upgrade: • 30 kHz accept rate all trck pT>2 GeV processing time SVX read out after L1 σ (IP) = 35 µ m, L2 σ (1/Pt) = 0.3 % buffer L2 SVT here Two Track Trigger σ ( φ 0)=1 mrad 4 events (TTT) IP>100 µ m L2 ObjectMon #100 SVTMonitor Slide Show Run:192424 Event: 11231427 # of Events:229465 Time: Wed Jan 19 13:50:56 2005 Ref.Run:-1 •Asynchromous 2 Stage Pipeline 0 D invariant mass L3 plot 2001 Events Event fit quality : 1 •20 µ s Latency mean of D 0 : 1.861 ± 0.000 sigma of D 0 : 0.015 ± 0.000 DAQ 0 number of D : 9292 s sig/backg : 0.78 x-sec : 3.96 nb 80 •1000 Hz accept rate 800 integ. lumin : 2344.4 nb -1 buffers 0 600 400 K s L3 Farm 40 200 L3: CPU farm Full event 0 1.8 1.85 1.9 1.8 1.85 1.9 GeV/c 2 2 GeV/c Reconstruction D 0 D0 0 Mass Storage Speed-optimized Wine&Cheese, Aug15 2008 7 offline code (~100 Hz)
Gaseous tracking chamber rebuilt from run I to run II to cope with luminosity x100 and for the first time a tracking LV1 trigger: eXtremelyFastTracker COT axial layers Good hit patterns are identified as segments, then segments are linked as tracks XFT 3D upgrade: Add info from stereo layers Fake rejection ~8 COT stereo layers Wine&Cheese, Aug15 2008 8
Upgrade SVT for luminosity Upgrade SVT for luminosity At 3x10 32 : 5 pile ups Upgrade: Faster SVT components and: 32Kpatterns → 512Kpatterns new AM. p p original system Fraction of ev. event + underlying event + pile-up upgraded system 0 20 60 100 140 180 Luminosity (xE30) Original SVT turned off above 90xE30 Upgraded SVT can run @high Lumi Good Data@ higher Luminosity More Data @ lower Luminosity Wine&Cheese, Aug15 2008 9
• HEAVY FLAVOUR WORLD HEAVY FLAVOUR WORLD • Heavy flavours flavours as probes for New Physics as probes for New Physics Heavy Bs Mixing and CP violation Bs Mixing and CP violation and a zest of and a zest of some rare B decays… … some rare B decays Wine&Cheese, Aug15 2008 10
HFP: CDF assets HFP: CDF assets dE/dx in drift chamber (1.5 σ CRUCIAL: @p>2 GeV/c) and TOF (2 σ TRIGGER @p<1.6 GeV/c) provide π /K & PID ID crucial in flavor tagging High muon acceptance Vertex (84% azimuthal at position |eta|<1.5) and precise known with muon ID ~25 µm uncertainty Calorimeter for electron ID used in flavor tagging XFT x SVT triggering Excellent vertexing to resolve fast oscillations (silicon detector) and momentum resolution for improving S/B (large radius drift chamber) immersed in 1.4 T B field. Wine&Cheese, Aug15 2008 11
Welcome to the B s -world: Bs mesons = {bs} bound states A b b R N E Transitions Matter ↔ Antimatter via: NEW PHYSICS? T T I T M s s A A M T T 0 E B s 0 B s R System defined by 5 parameters: Masses: m H , m L Lifetimes: Γ H , Γ L ( Γ =1/ τ ), Phase: Φ s Bs observables: ∆ m s = m H -m L ≈ 2IM 12 I defines mixing oscillation frequency Different Lifetimes: ∆ Γ s = Γ L -Γ H ≈ 2 I Γ 12 I cos Φ s SM = arg(-M 12 / Γ 12 ) ≈ 0.24 0 : small value predicted by SM CPviolating phase: Φ s Wine&Cheese, Aug15 2008 12
∆ m s measurement PRL. 97, 242003 (2006) ∆ m s = 17.77±0.10(stat) ± 0.07(syst) ps -1 Extracted parameters dominated by theoretical errors; Need more from LQCD |V ts / V td |= 0.2060 ± 0.0007 (exp) + 0.0081 (theo) 1 fb -1 -0.0060 (5.4 σ significance) CDF present focus ∆Γ S = Γ H - Γ L , Γ= ( Γ H + Γ L )/2 and β s ALL in ONE process β s = phase of b → ccs transition accounts for decay & mixing+decay= 2.2 0 (SM prediction) SM + Φ s NP and 2 β s = 2 β s SM – Φ s If NP occurs in mixing: Φ s = Φ s NP � standard approximation: Φ s = -2 β s Wine&Cheese, Aug15 2008 13
β S measurement in B s → J/ ΨΦ : analyse overview Courtesy Diego Tonelli B 0 s → J/ ψ ( → µ+µ-) Φ ( → K+K-) K + Vertex known at K - Infer flavor at production from Φ ~25 µm Sensitivity to phase increases if CP- other objects in the event odd and CP-even final states are µ - J/ ψ treated separately µ + Combine everything in a p p J/ ψ Φ Infer CP from t-dependent Maximum Likelihood fit angular distributions Measure decay time from flight Sensitivity to phase increases if ℓ = 0 B 0 length mesons of different production flavor – s µ + µ - K + K - are treated separately ℓ = 1 B 0 ℓ = 2 s Wine&Cheese, Aug15 2008 14
Signal extraction and CP-determination 1.4/fb, ~2000 decays, S/B~2 B 0 s → J/ ψ ( → µ + µ - ) Φ ( → K + K - ) NN maximizes S/ √ (S+B). Trained on MC for signal and mass-sidebands for background. Determine CP of final state from angular correlations. Wine&Cheese, Aug15 2008 15
Flavour-tagging performance Same tagging used successfully for mixing-frequency measurement Opposite Side: looks at decay of the ‘other’ b -hadron in the event Same Side: exploits the charge/species correlations with associated particles produced in hadronization of reconstructed B 0 s meson OST efficiency: 96±1% SST efficiency: 50±1% Output: decision ( b -quark or anti b -quark) and the probab. of being correct Wine&Cheese, Aug15 2008 16
Wrapping up all together in a fit Angles Mass Decay-time Tagging MC and data MC (signal) and exponential (signal) (signal), sidebands sideband data empirical model for (background) (background) background Wine&Cheese, Aug15 2008 17
Data-driven checks (and results!) Angles Mass-lifetime Flavor tagging OST tuned on B + SST tuned on MC, checked on mixing measurement ‘a posteriori’ Measurt w/o flavor tagging c τ s = 459 ± 12 (stat) ± 3 (sys) µ m Measured polarization of ∆Γ = 0.02 ± 0.05 (stat) ± 0.01 (sys) ps -1 B 0 →ψ K*: consistent w/ B- PRL 100, 121803 (2008) Pred.0.096± 0.039ps -1 factories (and competitive!) Wine&Cheese, Aug15 2008 18
Results PRL100, 161802(2008) Assuming the SM, the probability of observing a fluctuation as large or larger than observed in data is 15% (1.5 σ ) One dimensional: 0.16 < β s < 1.41 at 68% CL Wine&Cheese, Aug15 2008 19
ICHEP update 3200 decays, S/B~2 N.B. Analysis not yet optimized 0.28 < β s < 1.29 at 68% CL Increased dataset still hints at larger than SM values! Consistency with SM decreased 15% � 7% (~1.8 σ ) www-cdf.fnal.gov/physics/new/bottom/080724.blessed-tagged_BsJPsiPhi_update_prelim/ Wine&Cheese, Aug15 2008 20
LOOK for 2- -body B, D rare decays at CDF: body B, D rare decays at CDF: LOOK for 2 B 0d,s → µµ, B 0d,s → eµ, B 0d,s → ee and D 0 → µµ Ex: SM=> BR(B s → µµ)~3.8x10 -9 But WHY: WHY: BR enhanced by x10-10 3 by NP FCNC decays forbidden at tree level, proceed through loops. FCNC decays forbidden at tree level, proceed through loops. Higher order diagrams highly suppressed, allowing NP to manifest itself. Higher order diagrams highly suppressed, allowing NP to manifest itself. Wine&Cheese, Aug15 2008 21
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