- For the public
- Teachers and pupils
In the last 15 years several experiments contributed an explosion of new results on heavy QCD bound states. Today, we potentially stand at the beginning of a new wave of discoveries, with the Belle II experiment about to start the data taking, BESIII moving forward into its program and the LHC experiments moving into their next phase. These new experiments, collecting much larger statistics, will not only allow to constrain the low energy QCD models, but also to study rare decays sensitive to new physics scenarios. We will present here an overview of the opportunities given by a data taking at the $\Upislon(3S)$ energy by the Belle II experiment, with a focus on the rare and invisible decays sensitive to new physics, and on the light dark matter searches.