ZZ Fusion Analysis

Neural Network training

We use the flavour tagging package LCFIVertex. This package consists of a topological vertex finder ZVTOP, which reconstructs secondary interactions, and a multivariate classifier which combines several jet-related variables to tag bottom, charm, and light quark jets.

Our steering file will contain the following LCFI component processors and a neural net trainer:

  <group name="JetFinders"/>
  <group name="MyTrueAngularJetFlavourProcessorCollection"/>
  <processor name="IPRPCutProcessor"/>
  <processor name="MyPerEventIPFitterProcessor"/>
  <processor name="ZVRESRPCutProcessor"/>
  <processor name="MyZVTOP_ZVRES"/>
  <processor name="FTRPCutProcessor"/>
  <processor name="MyFlavourTagInputsProcessor"/>
  <processor name="MyNeuralNetTrainer" type="GlasgowNeuralNetTrainer"/>

These processors have the following functions:

• IPRPCut - selects Reconstructed Particles based on track parameters, number of hits etc.
• PerEventIPFitter - finds the event Impact Parameter
• ZVRESRP - vertex finder for reconstructed particles
• ZVTOP_ZVRES - topological vertex finder
• FTRPCut: - flavour tagging reconstructed particle cuts
• FlavourTagInputs - from vertices and tracks calculates discriminating variables for the neural net
• NeuralNetTrainer - trains the networks

The neural nets are saved as XML files in nnets/ and will be used for flavour tagging (next step). No slcio output is written at this time.

Flavour Tagging

• TrueJetFlavour - determines MC flavour of reconstructed jets

A new file containing with these collections added is saved to be used in our analysis.

Acceptance Studies

Four Jet Events

Purity and Efficiency Studies

Electrons from Hard Bremsstrahlung

Luminosity and Event Weights

-- DanProtopopescu - 2013-06-28