Neutral heavy lepton production at next high energye+e−linear colliders

Abstract

The discovery potential for detecting new heavy Majorana and Dirac neutrinos at some recently proposed high energy ${e}^{+}{e}^{\ensuremath{-}}$ colliders is discussed. These new particles are suggested by grand unified theories and superstring-inspired models. For these models the production of a single heavy neutrino is shown to be more relevant than pair production when comparing cross sections and neutrino mass ranges. The process ${e}^{+}{e}^{\ensuremath{-}}\ensuremath{\rightarrow}\ensuremath{\nu}{e}^{\ifmmode\pm\else\textpm\fi{}}{W}^{\ensuremath{\mp}}$ is calculated including on-shell and off-shell heavy neutrino effects. We present a detailed study of cross sections and distributions that shows a clear separation between the signal and standard model contributions, even after including hadronization effects.