Search for Long-Lived Heavy Neutrinos at the LHC with a VBF Trigger

TL;DR

This paper investigates the potential of using a vector boson fusion trigger at the LHC to detect long-lived heavy neutrinos, especially in scenarios lacking a charged lepton trigger, by analyzing displaced dilepton and jet signatures.

Contribution

It introduces a novel VBF trigger strategy for long-lived heavy neutrino detection at the LHC, applicable to both minimal and extended Seesaw models.

Findings

VBF trigger can effectively identify heavy neutrinos without charged lepton signals.

Displaced dilepton and multitrack jet searches are promising for these scenarios.

The approach broadens detection capabilities for long-lived neutrinos at the LHC.

Abstract

The charged current production of long-lived heavy neutrinos at the LHC can use a prompt charged lepton for triggering the measurement of the process. However, in order to fully characterize the heavy neutrino interactions, it is necessary to also probe Higgs or $Z$ mediated neutral current production. In this case the charged lepton is not available, so other means of triggering are required. In this work, we explore the possibility of using a vector boson fusion trigger in the context of a GeV-scale Type I Seesaw model. We consider a minimal model, where both Higgs and Z-mediated contributions produce one heavy neutrino, as well as an extended model where the Higgs can decay into two heavy ones. Both scenarios are tested through displaced dilepton and displaced multitrack jet searches.