Lepton number violation in heavy Higgs decays to sneutrinos

TL;DR

This paper explores the potential to observe lepton number violation via sneutrino oscillations in a supersymmetric model, proposing collider signatures and implications for neutrino Yukawa couplings.

Contribution

It introduces a novel mechanism for lepton number violation in the right-handed sneutrino sector within an extended supersymmetric model, linking collider signals to neutrino Yukawa couplings.

Findings

Sneutrino-antisneutrino oscillations can produce detectable LNV signatures at the LHC.

Resonant production of sneutrino pairs via a heavy Higgs is feasible.

Future collider signals could help determine neutrino Yukawa couplings.

Abstract

We study the possibility of observing lepton number violation in the right-handed sneutrino sector of the Next-to-Minimal Supersymmetric Standard Model extended with right-handed neutrinos. The scalar potential introduces a lepton number violating mass term for the right-handed sneutrinos, which generates a phase difference that results in oscillations between the sneutrino and antisneutrino. If we have light higgsinos and right-handed sneutrinos, the sneutrino decay width is determined by the tiny Yukawa couplings, which allows the phase difference to accumulate before the sneutrino decays. We investigate the possibilities of producing sneutrino pairs resonantly through a heavy Higgs of such a model and the ability of seeing a lepton number violating signature emerging from sneutrinos at the Large Hadron Collider. We also discuss how a possible future signal of this type could be used to determine the neutrino Yukawa couplings.