Vertex Displacements for Acausal Particles: Testing the Lee-Wick Standard Model at the LHC

Abstract

We propose to search for wrong displaced vertices, where decay products of the secondary vertex move towards the primary vertex instead of away from it, as a signature for microscopic violation of causality. We analyze in detail the leptonic sector of the recently proposed Lee-Wick Standard Model, which provides a well motivated framework to study acausal effects. We find that, assuming Minimal Flavor Violation, the Lee-Wick partners of the electron, {\tilde l}^e and \tilde e, can produce measurable wrong vertices at the LHC, the most promising channel being q \bar{q} --> \bar{\tilde l}^e {\tilde l}^e --> e^+ e^- jjjj. A Monte-Carlo simulation using MadGraph/MadEvent suggests that for M_l < 450 GeV the measurement of these acausal vertex displacements should be accessible in the LHC era.