phi puzzle in heavy-ion collisions at 2 AGeV: how many K-from phi decays?

The preliminary experimental data on $φ$ production in the reaction Ni(1.93 AGeV) + Ni point to a puzzling high $φ$ yield which can not be reproduced with present transport codes. We survey the experimental situation and present prospects for dedicated measurements of the $φ$ multiplicities with the $K^+ K^-$ and $e^+ e^-$ channels at HADES and FOPI.