Displaced heavy neutrinos from Z ' decays at the LHC

Abstract

We study the LHC sensitivity to probe a long-lived heavy neutrino N in the context of Z' models. We focus on displaced vertex signatures of N when pair produced via a Z', decaying to leptons and jets inside the inner trackers of the LHC experiments. We explore the LHC reach with current long-lived particle search strategies for either one or two displaced vertices in association with hadronic tracks or jets. We focus on two well-motivated models, namely, the minimal U(1)(B-L) scenario and its U(1)(X) extension. We find that searches for at least one displaced vertex can cover a significant portion of the parameter space, with light-heavy neutrino mixings as low as vertical bar V-lN vertical bar(2) approximate to 10(-17), and l = e, mu accessible across GeV scale heavy neutrino masses.