Study of scalar leptons at the TESLA photon collider

by Nieto-Chaupis, Huber

Abstract: In this thesis, the potential to discover supersymmetric signatures in both e+e- and gamma-gamma colliders evaluated with a Monte Carlo analysis, is discussed. The analysis was focused on the detection of muons, essentially. First, we study the detection of R-smuons in e-e+ collisions, whose purpose is the measurement of the smuon mass. It was found that an uncertainty of 0.11 GeV (stat) can be achieved. Under the assumption of the real conditions of the ILC photon collider, a study covering the detection of R-smuons and L-smuons pairs for a center-of-mass energy of e-e- = 0.5 and 0.6 TeV was performed. According to the simulation, a statistical error for the branching ratios of L-smuon -> muon neutralino1 of 0.98% and L-smuon -> muon + neutralino2 of 3.97% can be reached. In order to judge the Monte Carlo results, we have used a technique based on a multidimensional fit to evaluate the impact of the branching ratio measurements on the precision of the SUSY parameters. Furthermore, the possibility of identifying heavy neutralinos such as neutralino2 via detection of the muon+ muon- neutralino1 muon+ muon- neutralino1 and muon- e+ neutralino1 muon+ e- neutralino1 final states produced in gamma-gamma collisions, was explored. This study reveals that the photon collider will provide a remarkable amount of data for this topology, contrary to lepton colliders. Information acquired from energy distributions of final state leptons turns out to be enough to identify the supersymmetric signal. From the invariant mass scatter plots the mass difference of the supersymmetric particles involved in the cascades is determined. It is shown that the neutralino2 mass and the mass difference between neutralino2 and neutralino1 and L-smuon and R-smuon can be quite well estimated. Further potential sources of inherent systematic errors, are discussed.