Lepton Pair Production in Neutrino–Nucleus Scattering

The impact of the emission of new light gauge bosons in neutrino–nucleus scattering on the observed signal is studied. As an example, a model with a neutral vector boson $Z{}^{{}^{\prime }}$ with a mass of a few tens of MeV, interacting with neutrinos via the $V-A$ current, is considered. An equivalent $Z{}^{{}^{\prime }}$ boson spectrum for neutrinos is introduced. The corresponding correction to the total neutrino–nucleus scattering cross section as a function of the collision energy is calculated. This correction for several values of the model parameters allowed by the existing experimental bounds is presented.