Heavy-Majorana-neutrino production

Heavy-Majorana-neutrino production and detection at colliders is examined. Majorana-neutrino decay is shown to be simply calculable from Dirac-neutrino results. Majorana-neutrino production $f\overline{f}\to Z\to \mathrm{NN}$ is calculated and compared to Dirac-neutrino production. Near the threshold, the Dirac cross section rises much more quickly. Far above the threshold, the two types of neutrinos have the same spin-independent cross sections while the spin-dependent cross sections are very different. This difference could be observed in the correlations between the angle and energy dependence of the heavy-neutrino decay products.