The search for top quark pairs implying tau leptons in their decay products at the CDF detector, has two main goals:
To observe one of the last ttbar chanels yet to be observed, and to check for any disagreement with the standard model expectation. The signal is tiny and hard to extract witin a background dominated by Z->TauTau+2 jets events, and W+3 jets events in which one jet is misidentified as a hadronic tau decay. One of the main aspects of this thesis is the development of a rigorous method to estimate the leading background of W+jets within an environment with high jet multiplicity, high missing transverse energy, one electron or muon and one hadronic tau. The analysis was performed using two data samples totalizing integrated luminosities of 350/pb and 1/fb. After having carefully checked the coherence of the method used, a 76% evidence has been found for the top in tau signal. Also, the relative excess R of top signal as compared with the standard model value has been measured to be less than 1.5 at 95% confidence level. 


Posted to /cdf/www/pub/thesis/cdf9027_TourneurThesis.pdf
    http://www-cdf.fnal.gov/thesis/cdf9027_TourneurThesis.pdf

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