Signatures of NP models in top FCNC decay t --> c(u) l+ l-

TL;DR

This paper explores how top quark FCNC decays, specifically t --> c(u) l+ l-, can reveal signatures of new physics at the LHC, emphasizing asymmetries and interference effects to distinguish NP scenarios.

Contribution

It introduces a model-independent analysis of top FCNC decays, highlighting the potential of asymmetry measurements and interference effects to identify and differentiate new physics models.

Findings

Measurement of asymmetries can provide crucial information about NP.

Interference between scalar and vector mediators affects decay signatures.

Asymmetry analysis can discriminate among various NP scenarios.

Abstract

Among other roles the LHC will play a role of the top "factory" and it will give us unique possibility to study new physics signatures in different ways. Many scenarios of new physics allow top quark FCNC decays. Using most general model independent Lagrangian of new physics we investigate possible experimental signals of new physics in t --> c(u) l+ l- FCNC top decays. We find that measurement of two possible asymmetries might give very important and interesting information of NP. It is particularly interesting to use them to discriminate among variety on NP scenarios. We consider also contributions of the interference between scalar and vector mediators of the FCNC decays.