Phenomenology of top partners at the ILC

The assumption of a new symmetry provides a nice explanation of the existenceof dark matter and an elegant way to avoid the electroweak constraints. Thissymmetry often requires the pair production of new particles at colliders andit guarantees that cascade decays down to the lightest particle give rise tomissing energy plus jets and leptons. For a long time, supersymmetry with theconserved R-parity was the only candidate for such signals. However, any newphysics with this type of new symmetry may show up with similar signals and thediscrimination between different models at the LHC is quite challenging. Inthis paper, we address the problem of discrimination between different models,more concretely, in the little Higgs theory with T-parity (LHT) and thesupersymmetric theory with R-parity. We concentrate on the pair production ofheavy top partners, e.g., T-odd quarks in LHT and the scalar top quarks in theMSSM at linear colliders (LC).Comment: 21 pages, 12 figure