WW Scattering studies for the Future Linear Collider

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WW Scattering studies for the Future Linear
Collider

• Andres F. Osorio
• Postgraduate student
• High Energy Physics Group

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Contents
Motivation Work done/ preliminary
results Final remarks
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Motivation
To study WW scattering in the frame of the
Electroweak Chiral Langrangian at ee- colliders

• WLWL ?WLWL
• Sensitive to the physics of
• Electroweak Symmetry breaking
• Look for resonances (scalar, vector, )
• Compare with LHC

WW scattering at LHC, J. Butterworth, B. Cox,
J. Forshaw Strong Electroweak Symmetry Breaking
Signals in WW scattering at TESLA, R.
Chierici, S. Rosati, M. Kobel
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First steps

• Generating a SM Higgs of mass Mh0 300 GeV/c2
• C.M.E. of 800 GeV.
• Generating my events with Pythia 6.2
• Look for the 4 quarks final states using a jet
  finder algorithm
• No detector simulation for the moment

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Quick review
SM Higgs production at ee- collider
Higgs-strahlung WW fusion
SM Higgs decays modes
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Analysis

• Using the KT algorithm (C implementation)
• -gt E recombination scheme.
• -gt Force to have 4 jets.
• It is clear that this should work but Im having
  problems when I form pairs of jets and
  reconstruct the signal.
• -gtThis isnt working, so I had to perform a
  subjet analysis (using ycut set to 0.0005).

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Signal

• Selection
• Take all possible pairs of combinations of jets.
• Using the criteria
• Mij-MWMkl-MW
• take the minimum.

L 500 fb-1
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Background
L 500 fb-1
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Final remarks

• Its not yet well understood why the problem in
  having only 4 jets
• - Is it a problem with the generated events?
• - Is it a bug in the K?
• Lots of things to do
• - Refine the selection method and apply cuts
• - Work fully on the background signals (QCD?)
• - Study the angular distribution Cos (?)