Search potential for direct slepton pair production at the CEPC with $\sqrt{s}$ = 360 GeV

TL;DR

This study evaluates the potential of the CEPC at 360 GeV to discover direct production of sleptons, specifically staus and smuons, through detailed Monte Carlo simulations, highlighting its capability to probe new physics beyond the Standard Model.

Contribution

The paper provides the first sensitivity analysis for direct slepton pair production at the CEPC operating at 360 GeV, estimating discovery mass reach with systematic uncertainties considered.

Findings

CEPC-360GeV can potentially discover staus up to 170 GeV.

Discovery potential for smuons extends to 178 GeV.

Systematic uncertainties of 5% are included in the sensitivity estimates.

Abstract

The Circular Electron Positron Collider (CEPC) is designed to operate at the key center-of-mass energies: 91.2 GeV as a Z factory for precision Z boson studies,$\approx$ 160 GeV at the threshold for W boson pair production, and 240 GeV as a Higgs factory for copious Higgs boson production. It can be upgraded to 360 GeV (CEPC-360GeV) for enabling top quark-antiquark ($t\bar{t}$) pair production. Beyond enabling high-precision measurements of the Standard Model (SM), CEPC-360GeV is uniquely position to perform searches for new physics beyond the SM (BSM) physics, serving as a valuable complement to hadron colliders. This paper presents a sensitivity study on the direct pair production of staus and smuons at the CEPC with $\sqrt{s}$ = 360 GeV, conducted via full Monte Carlo (MC) simulation. Under the assumptions of integrated luminosity 1.0 ab^{-1} and a flat 5% systematic uncertainty, CEPC-360GeV could potentially discover the combined production of left-handed and right-handed staus up to a mass of 170 GeV (if they exist), or up to 169 GeV for pure left-handed staus and 162 GeV for pure right-handed staus. For direct smuon production, the discovery potential reaches up to 178 GeV under the same conditions.