FPCP 2003 : 3-6 June 2003 Ecole Polytechnique, Paris Status and Prospects of ATLAS and CMS for B Physics and CP Violation Fairouz Ohlsson-Malek LPSC-Grenoble/IN2P3/ATLAS 1 Status and Prospects of ATLAS and CMS for B Physics and CP Violation  Overview of the Detector Status  Overview of the physics potential  B physics reach: Trigger,Tagging and off-line strategies Precision physics Physics of B s meson Potential for rare decays B hadron production  Conclusions

FPCP 2003 : 3-6 June 2003 Ecole Polytechnique, Paris Status and Prospects of ATLAS and CMS for B Physics and CP Violation Fairouz Ohlsson-Malek LPSC-Grenoble/IN2P3/ATLAS 2 CMS detector 13x6 m Solenoid: 4 Tesla field tracking up to  ~ 2.4 tracking up to  ~ 2.4 Staged Scenario for start-up ME4 staged 3 rd forward pixel disks missing Descoped HCAL (reduced no. of longitudinal samplings) Descoped ME1/1a (3 ch in one, muon trigger up to |h| = 2.1) Effects on B-physics: limited trigger rate, degraded proper time resolution ECAL & HCAL inside solenoid 22 m long, 15 m diameter, ton

FPCP 2003 : 3-6 June 2003 Ecole Polytechnique, Paris Status and Prospects of ATLAS and CMS for B Physics and CP Violation Fairouz Ohlsson-Malek LPSC-Grenoble/IN2P3/ATLAS 3 ATLAS detector 46 m long, 25 m diameter and ~ kg ATLAS initial layout: 1 pixel layer, 1 forward pixel disk, TRT wheels C A significant fraction of HLT/DAQ processors deferred Effects on B-physics: limited trigger rate, degraded proper time resolution 2 Tesla field tracking up to  ~ 2.4 tracking up to  ~ 2.4

FPCP 2003 : 3-6 June 2003 Ecole Polytechnique, Paris Status and Prospects of ATLAS and CMS for B Physics and CP Violation Fairouz Ohlsson-Malek LPSC-Grenoble/IN2P3/ATLAS 4 LHC reach high detector granularity  large event size (O(1) MByte) high collision rate (~ 10 8 – 10 9 per sec ) Collision Energy14 TeV Design Luminosity10 34 cm -2 s -1 Interactions per Bunch Crossing  23 Bunch spacing25 ns B-meson decays, precise measurements CP violationCP violation B s mesonsB s mesons Rare decaysRare decays B-hadron production Double heavy flavor mesonsDouble heavy flavor mesons QCD tests of beauty production at LHC central regionQCD tests of beauty production at LHC central region Physics of Beauty baryons, production polarizationPhysics of Beauty baryons, production polarization

FPCP 2003 : 3-6 June 2003 Ecole Polytechnique, Paris Status and Prospects of ATLAS and CMS for B Physics and CP Violation Fairouz Ohlsson-Malek LPSC-Grenoble/IN2P3/ATLAS  b 230  b LHC  total = 100 mb  inelastic = 80 mb  bb = 500  b ATLAS & CMS Central detectors LHCb Forward detector |  | 10 GeV  B-hadron = 100  b GeV  B-hadron = 230  b L = 1-2 x cm -2 s cm -2 s -1 for rare decays L = 2 x cm -2 s -1 Exclusive channels ~ Dominated by bb  J/  Hadronic channels: < 10 5 (however all with muon tag) Exclusive channels ~ bb  J/  Hadronic channels ~ Overview of the B physics potential

FPCP 2003 : 3-6 June 2003 Ecole Polytechnique, Paris Status and Prospects of ATLAS and CMS for B Physics and CP Violation Fairouz Ohlsson-Malek LPSC-Grenoble/IN2P3/ATLAS 6 Trigger Strategies ATLASCMS Level 1 1  p T > 6 GeV, |  | <2.4 2  6 GeV 1  p T > 14 GeV, |  | <2.4 2  3 GeV  Level 2 Lepton reconstruction and Identification Track reconstruction either in full ID volume or in ROI followed by mass cuts on track combinations Event Filter Offline algorithms, Decay vertices cuts ….

FPCP 2003 : 3-6 June 2003 Ecole Polytechnique, Paris Status and Prospects of ATLAS and CMS for B Physics and CP Violation Fairouz Ohlsson-Malek LPSC-Grenoble/IN2P3/ATLAS 7 Trigger Strategies 2  trigger: LVL1: 2 , LVL2:  track in  spectrometer+Inner Bd  J/  (  ) Ks, Bs  J/  (  ) ,  b  J/  (  ) , B  , B  K* 0 , B    -e(  ) trigger: LVL1:  e    GeV , LVL2: tracking in region Bd  J/  (ee) Ks + B    b  J/  (ee)  + B    d    …  -hadron trigger: LVL1:  + jet (E T > 5 GeV), LVL2 tracking in region B   + B  , Bs  Ds  + B  , …. ATLAS as an example

FPCP 2003 : 3-6 June 2003 Ecole Polytechnique, Paris Status and Prospects of ATLAS and CMS for B Physics and CP Violation Fairouz Ohlsson-Malek LPSC-Grenoble/IN2P3/ATLAS 8 B Tagging strategies l B0B0 B0B0 D   K-K- b b d u d u B0B0 ++ Opposite side lepton tag: ATLASCMS Efficiency 4% (e+  ) 4% D 0.52(  ), 0.46 e 0.44 ATLASCMS Efficiency 82% (  ) 21% D 0.16(  ) 0.32 Same side pion (B** + fragmentation): ATLASCMS Efficiency 64% (  ) 65% D 0.17(  ) 0.18 Jet charge – same (ATLAS) and opposite (CMS) side:

FPCP 2003 : 3-6 June 2003 Ecole Polytechnique, Paris Status and Prospects of ATLAS and CMS for B Physics and CP Violation Fairouz Ohlsson-Malek LPSC-Grenoble/IN2P3/ATLAS 9 Precision measurements Benchmark channels : B d  J/  K s  sin2  B d   +  -   sensitivity B s  J/   weak phase  s,  s B s  D s  (a 1 )   m s B +  K + K +  -  Br Upper limit on Br= for cm -2 s -1

FPCP 2003 : 3-6 June 2003 Ecole Polytechnique, Paris Status and Prospects of ATLAS and CMS for B Physics and CP Violation Fairouz Ohlsson-Malek LPSC-Grenoble/IN2P3/ATLAS 10 Precision measurements cm -2 s -1 ATLASCMS N Triggered events N Offline events S/B ev ev ev ev 8  sin2  Lepton tags Jet/charge tags Total ATLAS+CMS cm -2 s -1 ATLAS+CMS cm -2 s -1 + LHCb, cm -2 s The case of B d  J/  K s   sin2  Systematics can be controlled with very high statistics using control samples such as B +  J/  K +

FPCP 2003 : 3-6 June 2003 Ecole Polytechnique, Paris Status and Prospects of ATLAS and CMS for B Physics and CP Violation Fairouz Ohlsson-Malek LPSC-Grenoble/IN2P3/ATLAS 11 Physics of B s mesons CP violation weak phase  s = 2  = 2 2   B s oscillation parameter  m s Precision on  s ~ 8-12%,  s Benchmark channels : B s  J/   B s  D s  B s  D s a 1 ATLASCMS Proper time resolution 51 fs (60%) 107 fs (40%) 70 fs  m s 5  meas. up to 36 ps ps -1 Measurable values up to  m s 22.5 ps ps cm -2 s -1

FPCP 2003 : 3-6 June 2003 Ecole Polytechnique, Paris Status and Prospects of ATLAS and CMS for B Physics and CP Violation Fairouz Ohlsson-Malek LPSC-Grenoble/IN2P3/ATLAS 12 Physics of B s mesons B s  J/   BR(B s  J/   )=(9.3±3.3)x10 -4 J/  ℓ + ℓ - (BR≈6%),  K + K (BR ≈ 49%) HLT mass resolutions  = 22.4 MeV  = 2.2 MeV  = 46.5 MeV J/   BsBsBsBs CMS studies Lvl-1  Lvl-2  Lvl-2 Rate Lvl-3  Lvl-3 Rate Events/ 10fb %13.7% 14.5 Hz 8.7%<1.7Hz83800

FPCP 2003 : 3-6 June 2003 Ecole Polytechnique, Paris Status and Prospects of ATLAS and CMS for B Physics and CP Violation Fairouz Ohlsson-Malek LPSC-Grenoble/IN2P3/ATLAS 13 Physics of B s mesons Benchmark channels : B s  J/   B s  J/   s = 2  = 2 2  SM predicts  s ~ O(0.03)  New Physics S/B >~1.  Experimental lower limit Theory: ATLAS studies B s  J/ 

FPCP 2003 : 3-6 June 2003 Ecole Polytechnique, Paris Status and Prospects of ATLAS and CMS for B Physics and CP Violation Fairouz Ohlsson-Malek LPSC-Grenoble/IN2P3/ATLAS 14 Potential for studying rare decays FCNC b  s or b  d only at loop-level in SM Br < O(10 -5 ) B  K* , B   , B  , B  K* , …. bs,d W-W-  u,c,t bs,d  ? Sensitive to new physics : New diagrams appearing :charged Higgs, chargino, squark contributions |V td | |V ts | in SM Complementary determination from  m s

FPCP 2003 : 3-6 June 2003 Ecole Polytechnique, Paris Status and Prospects of ATLAS and CMS for B Physics and CP Violation Fairouz Ohlsson-Malek LPSC-Grenoble/IN2P3/ATLAS 15 Potential for studying rare decays The case of B  K*  B  K*  ATLAS1995 CMS4200 5% precision on A FB after 3 low lumi SM MSSM C7  >0 MSSM C7  <0 Three points: mean values of A FB in three q 2 /M B 2 experimental regions with error bars

FPCP 2003 : 3-6 June 2003 Ecole Polytechnique, Paris Status and Prospects of ATLAS and CMS for B Physics and CP Violation Fairouz Ohlsson-Malek LPSC-Grenoble/IN2P3/ATLAS 16 Potential for studying rare decays The case of B  Mass resolution HLT FullTracker  = 46 MeV  = 74 MeV CMS studies for B s   Offline analysis results (hep-ph/ ), using SM BR=3.5x10 -9 (Lvl-1 trigger in |  |<2.4 instead of |  |< 2.1) 10 fb -1 => 7 signal events with <1 background 5  observation with 30 fb -1 and analysis could be perfomed at high lumi too B s   B d   Background ATLAS CMS 264.1< cm -2 s -1

FPCP 2003 : 3-6 June 2003 Ecole Polytechnique, Paris Status and Prospects of ATLAS and CMS for B Physics and CP Violation Fairouz Ohlsson-Malek LPSC-Grenoble/IN2P3/ATLAS 17 Potential for studying rare decays exploring more difficult modes: B d  K*  ATLAS studies S BS B ~ 19 Level 1:  6 Level 2:  cluster candidate is selected if Cluster Et > 4 GeV 0.5 strips  cluster width  3.5 strips Energy leakage in  direction  9 % Energy leakage in  direction  9 % Energy proportion of strips 2 nd maximum  6% 2 nd maximum physical meaning  1.5% Shower shape  /  0 rejection Very preliminary

FPCP 2003 : 3-6 June 2003 Ecole Polytechnique, Paris Status and Prospects of ATLAS and CMS for B Physics and CP Violation Fairouz Ohlsson-Malek LPSC-Grenoble/IN2P3/ATLAS 18 B hadron production at LHC QCD Semihard PYTHIA CDF measurement of b-b correlation using  - b-jet data and comparison to models QCD - NLO describe the shape of differential cross section however underestimates absolute value of cross section by factor ~2.4 The case with Fermilab

FPCP 2003 : 3-6 June 2003 Ecole Polytechnique, Paris Status and Prospects of ATLAS and CMS for B Physics and CP Violation Fairouz Ohlsson-Malek LPSC-Grenoble/IN2P3/ATLAS 19 B hadron production at LHC ATLAS - proposal for measurement of b-b production correlations using exlusive B-decay and semi leptonic decay to muon: B  B d  J/  K s 0, B  B s  J/  No degradation of efficiency as b-b close in space.  =  J/  -  

FPCP 2003 : 3-6 June 2003 Ecole Polytechnique, Paris Status and Prospects of ATLAS and CMS for B Physics and CP Violation Fairouz Ohlsson-Malek LPSC-Grenoble/IN2P3/ATLAS 20 Conclusions General purpose central LHC detectors ATLAS and CMS are well equipped for multi thematic B-physics program - including B-decays and B-production. 1.In CP violation the main emphasis will be on underlying mechanisms and evidence of New physics. ATLAS and CMS are especially precise in measurement of . LHC ‘gold-plated’ mode is also B s  J/   2. B s mixing studies make clear that there is sensitivity to  m s far beyond SM expectations. The width difference  s can be measured best in B s  J/   with relative precision 8%. 3.Rare decays B  have the most favorable experimental signature allowing to measure also at nominal LHC luminosity cm -2 s -1. Will measure branching ration of B s   which is in SM of order Br<(10 -9 ). Precision measurements will be done for B  K* . 4. Beauty production and correlations at central LHC collisions will be measured for QCD tests. The program includes baryon production polarization 5.ATLAS and CMS beauty trigger strategies will be adapted according to luminosity conditions at initial LHC period.