Four-top production and t tbar + missing energy events at multi TeV e+e- colliders

TL;DR

This paper explores how new U(1)' gauge bosons in SM extensions could produce distinctive four-top and top pair plus missing energy signals at 3 TeV e+e- colliders, offering potential probes of beyond-the-Standard-Model physics.

Contribution

It analyzes collider signatures of Z' production in models with suppressed couplings to light SM states, focusing on four-top and ttbar+missing energy events at high-energy e+e- colliders.

Findings

Potential for striking four-top signatures at 3 TeV colliders

Enhanced ttbar+missing energy signals in specific SM extensions

Models are weakly constrained but produce distinctive collider signatures

Abstract

Four-top production and top pair production in association with missing energy at e+e- colliders are sensitive probes of beyond-the-Standard-Model physics. We consider Standard Model (SM) extensions containing a new U(1)' which couples preferably to the most massive states of the SM such as the top quark or Dark Matter but has suppressed couplings to all the light states of the SM, as inspired by Randall-Sundrum-like setups or theories of partial fermion compositeness. These simple models are poorly constrained by experimental data but lead to striking new signatures at colliders. In this note we consider Z' production in association with a top quark pair in 3 TeV e+e- collisions at CLIC, leading to interesting four-top final states and ttbar+missing energy events.