An overview of $η$ and $η^{\prime}$ decays at BESIII

Abstract

The world's largest sample of 1.31 billion $J/ψ$ events accumulated at the BESIII detector, provides a unique opportunity to investigate $η$ and $η^\prime$ physics via two body $J/ψ$ radiative or hadronic decays. For many $η^\prime$ decay channels the low background data samples are up to three orders of magnitude larger than collected in any previous experiment. Here we review the most significant results on $η$ and $η^\prime$ obtained at BESIII so far. The analyses range from detailed studies of the common decays dynamics, observations of new radiative and Dalitz decays, and search for rare/forbidden decays with sensitivity up to $\cal{B}\sim 10^{-5}$. Finally, prospects of the forthcoming runs at $J/ψ$ peak for the $η$ and $η^\prime$ physics are discussed.