Prospects for light exotic scalar measurements at the e$^+$e$^-$ Higgs factory

TL;DR

This paper explores the potential to detect light exotic scalar particles at future electron-positron Higgs factories, focusing on their production and decay channels, which could reveal physics beyond the Standard Model.

Contribution

It provides an analysis of the prospects for observing light scalars at Higgs factories, considering various decay modes and coupling scenarios not fully constrained by current data.

Findings

Light scalars could be produced at Higgs factories if their couplings are sufficiently suppressed.

Different decay channels offer promising avenues for detection of these scalars.

Results indicate potential sensitivity to non-standard scalar properties at future experiments.

Abstract

The physics program of the Higgs factory will focus on measurements of the 125 GeV Higgs boson, with the Higgs-strahlung process being the dominant production channel at 250 GeV. However, production of extra light scalars is still not excluded by the existing experimental data, provided their coupling to the gauge bosons is sufficiently suppressed. Fermion couplings of such a scalar could also be very different from the SM predictions leading to non-standard decay paterns. Presented in this contribution are results from the ongoing studies on prospects of direct light scalar observation at future Higgs factory experiments in different decay channels.