Contents

• Contents
• List of Tables
• List of Figures
• Scope of the Thesis
• The Standard Model
  • Quarks
  • Leptons
  • Force mediating bosons
• Charm Physics and Weak Decays
  • The discovery of Charm
  • Weak decays
• Charmed Baryons
  • Spectroscopy of the -like baryons
  • Charmed hadron lifetimes
  • Excited charmed baryons
• The FOCUS Experiment
• The 800 GeV Proton Beam
  • Proton acceleration
  • Proton extraction
• The Wideband Photon Beamline
• The Photon Beam Tagging System
  • Electron beam tagging
  • RESH and POSH calorimeters
  • BGM calorimeter
• Target Configuration
• Silicon Microstrip Tracking
  • Embedded stations
  • Downstream stations
• Analysis Magnets
• Multiwire Proportional Chambers
• Straw Tube Chambers
• System
• Calorimetry
  • Inner Electromagnetic calorimeter
  • Outer Electromagnetic calorimeter
  • Hadron Calorimeter
• Muon Detectors
  • Inner Muon detector
  • Outer Muon detector
• Scintillating Hodoscopes
• The Trigger
• Data Acquisition System
• Reconstruction Algorithms
  • SSD tracking
  • PWC track reconstruction
  • Linking
  • Momentum determination
  • Vertexing
  • Vee (and ) reconstruction
  • Kink (and ) reconstruction
  • Cascade (and $\Omega^-$) reconstruction
  • Electromagnetic ($\gamma$ and $\pi^0$) reconstruction
  • Neutral hadron reconstruction
• Particle Identification
  • identification
  • Muon identification
  • Electron identification
• Data Processing
  • Event reconstruction (Pass1)
  • Event selection (Skim1)
  • Final event splitting (Skim2)
• Vertexing
  • Vertex confidence levels
  • Detachment ()
  • Primary isolation (ISO1)
  • Secondary isolation I (ISO2)
  • Secondary isolation II (ISO3)
• Identification
• Other Cuts
  • Momentum
  • Lifetime
• Improving Momentum Vectors
  • Refitting track momenta
  • Improving track directions
• Optimizing Cuts
• Theory of Baryon Masses
  • Contributions to isospin mass splittings
  • Theoretical predictions
• Measurements from Other Experiments
• Event Selection and Reconstruction
  • selection
  • and reconstruction
  • reconstruction
• Determining Systematic Errors
  • Background contributions and fitting methods
  • Reconstruction methods
  • Systematic reconstruction biases
  • Effect of the overall mass scale uncertainties
  • Mass differences as a function of
  • Systematic errors from ``split samples''
  • Total systematic error calculations
• Final Values and Comparisons
• Conclusions
• Theoretical Predictions of Widths
• First Evidence for a Non-zero Width
• Event Selection and Reconstruction
  • selection
  • and reconstruction
• Measurement Method
• Systematic Errors
  • Agreement between and data
  • Test of the method with $\Xi^0(1530)$
  • Split sample tests
  • Total Systematic Errors
• Possible Pitfalls of the Fitting Method
• Conclusions
• and Reconstruction
• Conclusion
• Introduction
• Theoretical Expectations
• The Search
  • expectations
  • reconstruction
  • Possible cuts
  • Signals from the data
• Conclusion
• Results and Comparisons
  • measurements
  • measurements
• Concluding Remarks
• Bibliography
• The Sample
• The Reconstruction Method
• Studies of topological cuts
• Momentum and mass cuts
• Other cuts
• Arbitration
• Conclusions
• Split Sample Systematics
• Fit Variant Systematics