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Branching Ratios from. and. Matthew Martin Johns Hopkins University for the CDF collaboration. Flavor Physics & CP Violation Ecole Polytechnique, Paris, France June 2003. Outline:. Motivation Branching Ratios at CDF Results from:. Conclusions. CDF plans a rich program of B-Physics:.
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Branching Ratios from and Matthew Martin Johns Hopkins University for the CDF collaboration Flavor Physics & CP Violation Ecole Polytechnique, Paris, France June 2003
Outline: • Motivation • Branching Ratios at CDF • Results from: • Conclusions M.Martin, Johns Hopkins for CDF, FPCP June 2003
CDF plans a rich program of B-Physics: • Precision study of the : • BR’s, mass and lifetime • Plan to observe or rule out SM mixing • Measure • Measure • The world’s largest sample: • BR’s, mass and lifetime • CP Violation searches • This program just beginning… M.Martin, Johns Hopkins for CDF, FPCP June 2003
NEW ! NEW ! What we know: PDG 2002: New results for: M.Martin, Johns Hopkins for CDF, FPCP June 2003
What we know: PDG 2002: NEW ! Nearly New results for: M.Martin, Johns Hopkins for CDF, FPCP June 2003
Interaction rate • Reduced to on Level 2 output. • Critical component : SVT impact parameter cuts. • 2 Tracks with Tracks per 10 µm 0 4000 8000 -500 -250 0 250 500 silicon trigger impact parameter (µm) Events per 0.5 µs 0 10000 20000 0 10 20 30 40 50 Silicon trigger latency (µs) Hadronic Level 2 Trigger: 35mm 33mm resol beam s = 48mm M.Martin, Johns Hopkins for CDF, FPCP June 2003
Branching Ratios at CDF: • Compare search mode to kinematically similar mode, eg: • Cancellation: • Systematics in Trigger and Reconstruction Efficiency. • Production fractions ( ): • LEP/CDF Combined. • Aim to measure at CDF. • Daughter BR’s : • Rely on existing measurements. • Future : CLEO-C • Plan to normalise to same channel Semileptonic M.Martin, Johns Hopkins for CDF, FPCP June 2003
Normalisation mode: • Same mode for: • Similar cuts to signal • also visible. M.Martin, Johns Hopkins for CDF, FPCP June 2003
Important Cuts: 2 Tracks required to be Trigger Tracks. mass constrained to PDG value Reconstructing: First Observation! M.Martin, Johns Hopkins for CDF, FPCP June 2003
Systematics: Uncertainty in due to fit. Uncertainty in M.Martin, Johns Hopkins for CDF, FPCP June 2003
Results: M.Martin, Johns Hopkins for CDF, FPCP June 2003
Reconstructing Important cuts: M.Martin, Johns Hopkins for CDF, FPCP June 2003
3Types of reflection: • 4-Prong Decays • (eg ) • Other decays • Everything else. • Normalise Reflection shape to measured • yield. b Reflections: M.Martin, Johns Hopkins for CDF, FPCP June 2003
Effect of dE/dX: M.Martin, Johns Hopkins for CDF, FPCP June 2003
Expected Systematics: M.Martin, Johns Hopkins for CDF, FPCP June 2003
Current Status: • Finalising reflection model measurement for EPS • Systematic uncertainty dominated by: M.Martin, Johns Hopkins for CDF, FPCP June 2003
Prospects for improving normalisation: Note : Hadronic Trigger Path M.Martin, Johns Hopkins for CDF, FPCP June 2003
Reconstructing • required to be trigger tracks. • Optimise offline Cuts on MC signal, data sideband: • Isolation: • Efficiency from data • Defined in a cone about the B axis: M.Martin, Johns Hopkins for CDF, FPCP June 2003
Different signal contributions: Monte Carlo: • Total width due to several different contributions. • on top of each other • Disentangle using: • Invt Mass • Relative momentum • PID { Kinematic Separation ← Most Important M.Martin, Johns Hopkins for CDF, FPCP June 2003
Kinematic separation: Monte Carlo: • Choose 2 variables: • Signal Likelihood: M.Martin, Johns Hopkins for CDF, FPCP June 2003
Particle ID : • calibrated on sample • Bachelor charge identifies daughters. M.Martin, Johns Hopkins for CDF, FPCP June 2003
Systematics: M.Martin, Johns Hopkins for CDF, FPCP June 2003
Current Results: Yields: PDG 2002: M.Martin, Johns Hopkins for CDF, FPCP June 2003
Conclusions: • CDF has robust signals in: • First measurement of relative BR • First observation of • Measurement of validates extraction procedure • Expect and for EPS • First steps toward an exciting programme in physics and physics (mixing and CPV) . M.Martin, Johns Hopkins for CDF, FPCP June 2003