Lepton flavour violating stau decays versus seesaw parameters: correlations and expected number of events for both seesaw type-I and II

TL;DR

This paper explores how measurements of lepton flavor violating stau decays at the LHC can provide insights into the seesaw mechanisms (types I and II) responsible for neutrino mass generation, by analyzing correlations with neutrino parameters and estimating event rates.

Contribution

It establishes correlations between seesaw parameters and LFV decay ratios in mSugra, and identifies regions where LFV stau decays are maximized for both seesaw types, with event rate estimates.

Findings

Ratios of LFV decay rates correlate with neutrino oscillation parameters in specific scenarios.

Maximized LFV stau decay rates are identified within the mSugra parameter space.

Estimated number of LFV events at the LHC for 100 fb^{-1} luminosity.

Abstract

In minimal supergravity (mSugra), the neutrino sector is related to the slepton sector by means of the renormalization group equations. This opens a door to indirectly test the neutrino sector via measurements at the LHC. Concretely, for the simplest seesaw type-I, we present the correlations between seesaw parameters and ratio of stau lepton flavour violating (LFV) branching ratios. We find some simple, extreme scenarios for the unknown right-handed parameters, where ratios of LFV rates correlate with neutrino oscillation parameters. On the other hand, we scan the mSugra parameter space, for both seesaw type-I and II, to find regions where LFV stau decays can be maximized, while respecting low-energy experimental bounds. We estimate the expected number of events at the LHC for a sample luminosity of L = 100 fb^{-1}.