Prospects for Detecting light bosons at the FCC-ee and CEPC

TL;DR

This paper evaluates the potential for future Z-factory colliders like FCC-ee and CEPC to detect light bosons, focusing on specific production channels and their discovery prospects.

Contribution

It analyzes detection prospects for light bosons at future colliders, highlighting promising channels and background considerations for scalar and vector bosons.

Findings

Certain channels like Z→f f̄ X and Z→V_Q X are promising for discovery.

Large Z boson yields enable sensitive searches for light bosons.

Some channels are dominated by backgrounds and are less useful.

Abstract

We look at the prospects for detecting light bosons, $X$, at proposed Z factories assuming a production of $10^{12}$ Z bosons. Such a large yield is within the design goals of future FCC-ee and CEPC colliders. Specifically we look at the cases where $X$ is either a singlet scalar which mixes with the standard model Higgs or a vector boson with mass $1\lesssim M_X \lesssim 80$ GeV. We find that several channels are particularly promising for discovery prospects. In particular $Z\rightarrow f \bar{f} X$ and $Z \rightarrow V_Q X$ gives a promising signal above a very clean standard model background. We also discuss several channels that have too large a background to be useful.