Extraction of neutrino Yukawa parameters from displaced vertices of sneutrinos

TL;DR

This paper explores how displaced vertices of sneutrinos at the LHC can be used to extract neutrino Yukawa parameters, linking collider signatures to the neutrino mass generation mechanism in a supersymmetric model.

Contribution

It demonstrates a method to determine neutrino Yukawa couplings from displaced vertex measurements in a supersymmetric model with right-handed neutrinos.

Findings

Displaced sneutrino signatures can be observed at the LHC.

Yukawa parameters can be extracted from kinematic fits of displaced vertices.

Results are applicable to both current and High-Luminosity LHC data.

Abstract

We study displaced signatures of sneutrino pairs potentially emerging at the Large Hadron Collider (LHC) in a Next-to-Minimal Supersymmetric Standard Model supplemented with right-handed neutrinos triggering a Type-I seesaw mechanism. We show how such signatures can be established through a heavy Higgs portal in the presence of both leptonic and hadronic decays of the sneutrinos. We finally illustrate how the Yukawa parameters of the latter can be extracted from fitting kinematical quantities pertaining to the corresponding two displaced vertices, thereby characterising the dynamics of the underlying mechanism of neutrino mass generation. We show our numerical results for the case of both the current and High-Luminosity LHC.