Heavy Neutral Lepton searches at an ICARUS-like detector using NuMI beam

Abstract

The discovery of non-zero neutrino masses points to the likely existence of multiple SM neutral fermions. When such states are heavy enough that they cannot be produced in oscillations, they are referred to as Heavy Neutral Leptons (HNLs). In minimal models, the HNL production and decay are controlled by SM interactions and the mixing between HNLs and the active neutrino and typically result in relatively long lifetimes if the masses are in the MeV-GeV range. We have studied the physics case and technical feasibility for a dedicated HNL search using the NuMI beam at an ICARUS-like detector. Our analysis conclusively demonstrates that the constraints on the mixing of the HNL as a function of its mass for an ICARUS-like detector with NuMI beam are highly competitive with the limits obtained from present experiments.

Comments: v2 - Published in EPJ C. This version includes two appendices: one presenting the prediction of the light neutrino flux and another discussing the kinematical cuts that have been implemented. The paper consists of 14 pages and contains 6 figures