PhD Thesis of Armin Koengeter

Fakultaet fuer Physik
Universitaet Karlsruhe

Advisor: Prof Th. Muller
Co-Advisor Prof J. Hauser

Title (german): Suche nach Supersymmetrie mit Verletzung der R-Paritaet
                im 4--Leptonen--Kanal bei CDF

Title (english): Search for R-Parity violating SUSY
                 in the CDF Multi-Lepton channel

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The file Thesis_english.ps contains the ENGLISH thesis

The file Thesis_german.ps contains a summary in GERMAN

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Abstract:

In this Thesis a search for R-parity violating SUSY in the multi lepton
channel in CDF run IB data is presented . This is the first search in
this channel performed at a hadron collider. 

We assume the existence of a coupling violating
R-parity and lepton number conservation. If the coupling is 
small, the cascade decays of squarks, gluinos and bosinos to the 
lightest neutralino
will only be changed slightly by this new coupling.
These decays then can be handled within the R-parity conserving mSUGRA.
In addition to the processes from the R-parity conserving mSUGRA,
we consider the R-parity violating decay of the lightest
neutralino into two charged leptons and one neutrino.

Finding 1 event in 87.5 pb$^{-1}$ all scenarios yielding 5.1 or more events
are excluded, limiting $\rp$ violating minimal SUGRA models with a non-zero
coupling $\lambda_{121}$ to  $M_{1/2}{> \atop \sim} 130$ GeV.
This corresponds to a mass of the lightest neutralino of ${> \atop \sim}55$ GeV,
while the masses of the second lightest neutralino and the lightest chargino
are excluded up to 118 GeV$/c^2$.
The squarks and gluinos are excluded up to
squark (gluino) masses of ${> \atop \sim}$360 GeV (${> \atop \sim}$380 GeV).


Posted to:
  /cdf/pub/thesis/cdf5212_fourlepton_thesis_1.ps
      http://www-cdf.fnal.gov/thesis/cdf5212_fourlepton_thesis_1.ps
  /cdf/pub/thesis/cdf5212_fourlepton_thesis_2.ps
      http://www-cdf.fnal.gov/thesis/cdf5212_fourlepton_thesis_2.ps

Posted by koen@cdfsga