Sensitivity of the FACET experiment to Heavy Neutral Leptons and Dark Scalars

TL;DR

This paper evaluates the FACET experiment's ability to detect new physics, specifically Higgs-like scalars and Heavy Neutral Leptons, and compares its sensitivity with other proposed experiments.

Contribution

It introduces the potential of the FACET experiment to explore new physics parameter space beyond current constraints and existing proposals.

Findings

FACET can probe parameter space between current limits and other experiments.

FACET shows competitive sensitivity to Higgs-like scalars and Heavy Neutral Leptons.

The analysis highlights FACET's potential in the intensity frontier of particle physics.

Abstract

We analyze the potential of the recently proposed experiment FACET (Forward-Aperture CMS ExTension) to search for new physics. As an example, we consider the models of Higgs-like scalars with cubic and quartic interactions and Heavy Neutral Leptons. We compare the sensitivity of FACET with that of other proposed "intensity frontier" experiments, including FASER2, SHiP, etc. and demonstrate that FACET could probe an interesting parameter space between the current constraints and the potential reach of the above mentioned proposals.