Flavour violating bosonic squark decays at LHC

TL;DR

This paper investigates quark flavour violation in squark decays within the MSSM, showing that certain QFV decay channels can have large branching ratios and produce distinctive signals at the LHC, affecting supersymmetry searches.

Contribution

It demonstrates that QFV bosonic squark decays can have significant branching ratios due to large mixing and couplings, impacting LHC search strategies.

Findings

QFV decay branching ratios can reach up to 50%.

Characteristic QFV final states are predicted at the LHC.

QFV decays influence squark and gluino search strategies.

Abstract

We study quark flavour violation (QFV) in the squark sector of the Minimal Supersymmetric Standard Model (MSSM). We assume mixing between the second and the third squark generations, i.e. sc_R-st_{L,R} mixing mixing. We focus on QFV effects in bosonic squark decays, in particular on the decay into the lightest Higgs boson h0, su_2 -> su_1 h0, where su_{1,2} are the lightest up-type squarks. We show that the branching ratio of this QFV decay can be quite large (up to 50 %) due to large QFV trilinear couplings, and large sc_R-st_{L, R} and st_L-st_R mixing, despite the strong constraints on QFV from B meson data. This can result in characteristic QFV final states with significant rates at LHC (14 TeV), such as pp -> gluino gluino X -> t + h0 + 3jets + Etmiss + X and pp -> gluino gluino X -> t t (or tbar tbar) + h0 + 2jets + Etmiss + X. The QFV bosonic squark decays can have an influence on the squark and gluino searches at LHC.