Anomalous production of fourth-family up-quarks at future lepton hadron colliders

We have investigated the production of fourth-family up-type quarks using effective Lagrangian approach at future lepton-hadron colliders and study the kinematical characteristics of the signal with an optimal set of cuts. We have shown that the reaction eq → eu4 can take place at an observable rate at these colliders. The fourth-family up-quark will manifest itself at THERA and Linac-LHC with masses below 500 GeV and 1 TeV respectively. Thus the future lepton-hadron colliders have promising potential in searching for manifestations of non-standard physics. (authors)