Measuring neutrino dynamics in NMSSM with a right-handed sneutrino LSP at the ILC

TL;DR

This paper explores how future electron-positron colliders can measure neutrino Yukawa couplings in a non-minimal supersymmetric model with a light right-handed sneutrino dark matter candidate, using a clean dijet+dilepton+MET signature.

Contribution

It demonstrates the potential to extract neutrino Yukawa couplings in NMSSM with right-handed sneutrino dark matter at future colliders, highlighting a distinctive light bosonic DM candidate.

Findings

Light sneutrino DM can be produced at 500 GeV colliders.

Chargino decay signatures allow Yukawa coupling measurements.

Results motivate searches for light DM at future accelerators.

Abstract

We study the possibility of measuring neutrino Yukawa couplings in the Next-to-Minimal Supersymmetric Standard Model with right-handed neutrinos (NMSSMr) when the lightest Supersymmetric partner (a right-handed sneutrino) is the Dark Matter (DM) candidate, by exploiting a `dijet + dilepton + Missing Transverse Energy' (MET) signature. We show that, unlike the miminal realisation of Supersymmetry (SUSY), i.e., the MSSM, for which the DM candidate is a much heavier (fermionic) state (a neutralino), this non-minimal SUSY model offers one with a much lighter (bosonic) state (a sneutrino) as DM, which can be produced at future $e^+e^-$ colliders with energies up to about 500 GeV. The emerging signal, from chargino pair production and subsequent decay, is extremely pure so it allows for the possibility of extracting the Yukawa parameters of the (s)neutrino sector. These results should then motivate searches for light DM signals at such accelerators, where a DM candidate with mass at the Electro-Weak (EW) scale can then be accessed.