Search for the Decay $B_s^0 \rightarrow \eta^\prime \eta$

TL;DR

This paper reports the first search for the rare decay $B_s^0 ightarrow extit{eta'} extit{eta}$, using Belle data, resulting in no significant signal and setting an upper limit on its branching fraction.

Contribution

It provides the first experimental search for the decay $B_s^0 ightarrow extit{eta'} extit{eta}$ and establishes an upper limit on its branching fraction.

Findings

No significant signal observed.

Upper limit on branching fraction set at $6.5 imes 10^{-5}$.

First experimental constraint on this decay mode.

Abstract

We report the results of the first search for the decay $B_s^0 \rightarrow \eta^\prime \eta$ using $121.4~\textrm{fb}^{-1}$ of data collected at the $\Upsilon(5S)$ resonance with the Belle detector at the KEKB asymmetric-energy $e^+e^-$ collider. We observe no significant signal and set a 90\% confidence-level upper limit of %$7.1 \times 10^{-5}$ $6.5 \times 10^{-5}$ on the branching fraction of this decay.