$CP$ violating mode of the stoponium decay into $Zh$

TL;DR

This paper explores a new $CP$ violating decay mode of stoponium into $Zh$, which could have a significant branching ratio and be detectable at the LHC, even under EDM constraints.

Contribution

It demonstrates that the $Zh$ decay mode of stoponium can have a sizable branching ratio due to $CP$ violation in the stop sector, despite EDM constraints.

Findings

Branching ratio of up to 10% for $Zh$ decay mode.

Potential detectability at the LHC.

Significant $CP$ violation effects in stoponium decay.

Abstract

We show that a novel decay mode $Zh$ of the bound state of stop-anti-stop pair in the ground state $^1S_0(\widetilde t_1\widetilde t_1^*)$ may have a significant branching ratio if the $CP$ violating mixing appears in the stop sector, even after we apply the stringent constraint from the measurement of the electric dipole moment (EDM) of the electron. We show that the branching ratio can be as large as 10% in some parameter space that it may be detectable at the LHC.