Identification of the tau lepton through its hadronic decay modes at the DO collider detector
Padley, B. Paul
Master of Science
This thesis focuses on tau identification efficiencies in Monte Carlo simulations of various processes by implementing optimization techniques to determine optimal values for selection cuts on discriminant variables. Two sets of discriminants were studied: the first set consisted of only the Fisher discriminant, and the second set comprised the jet width and profile. Results obtained for the two sets are comparable for the central region (|eta| < 1.1) of the DO detector. For the forward region (|eta| ≥ 1.1), the optimization procedure did not yield optimal values for the set of variables used, suggesting that the signatures of the tau decay products in the forward regions is different from that in the central region, so that it appears that a different approach is required to identify the tau in the forward region. Given that the tau is to be identified through a reconstruction of its decay products, the complex interplay of the multitude of variables that need to be taken into account make the task of tau identification an ideal candidate for a multivariate analysis.
Particle physics; Elementary particles; High energy physics