SINGLE DILEPTION PRODUCTION AT E+E-, E-GAMMA, AND GAMMA-GAMMA COLLIDERS

We calculate the cross sections for the single production of doubly charged dileptons, both scalar and vector, at e+e-, egamma, and gammgamma colliders at square-root s = 500 GeV and 1 TeV. The egamma mode is by far the most promising-dileptons whose coupling is as weak as approximately 10(-4) alpha(m) can be observed, for masses virtually up to the kinematic limit. Dileptons of mass up to square-root s can also be seen in e+e- and gammagamma colliders, for couplings of order alpha(em). In all three colliders, most of the cross section comes from events in which the only particles detected are e-e- (or mu-mu- or tau-tau-), the decay products of the dilepton, yielding an unmistakable experimental signature.