Scalar radiation zeros at the LHC

TL;DR

This paper explores a class of singlet scalar extensions to the Standard Model where the scalar couples only to off-shell states, leading to vanishing low-order processes and unique collider phenomenology.

Contribution

It introduces a novel class of singlet scalars with off-shell couplings, proposing new search strategies at the LHC and identifying unexplored parameter space.

Findings

Tree-level processes involving the scalar vanish due to off-shell couplings.

Search strategies at the LHC can probe previously inaccessible parameter regions.

The model can evade existing constraints on singlet scalars.

Abstract

We consider a class of singlet scalar extensions of the Standard Model of particle physics in which the scalar couples only to off-shell states. As a result, low-order tree-level processes involving the singlet scalar vanish, providing a unique phenomenology that may allow to evade existing constraints on new singlet scalar fields. We describe search strategies for such states at the Large Hadron Collider and identify the parameter space that can be explored in the future.