From $\bar{K}N$ Interactions to $\bar{K}$-Nuclear Quasi-Bound States

We review the current status of our study of $K^{-}$-nuclear interactions and $K^{-}$-nuclear quasi-bound states. The adopted $K^{-}$-nuclear optical potential consists of two parts – the single-nucleon one constructed microscopically from chirally motivated $\bar{K}N$ amplitudes, and a phenomenological multi-nucleon one constrained in fits to kaonic atoms data. The inclusion of multi-nucleon absorption in our calculations of $K^{-}$ quasi-bound states in many-body systems leads to huge widths, considerably exceeding the binding energies. If this feature is confirmed the observation of such states is unlikely. Finally, a development of a new microscopical model for in-medium $K^{-}NN$ absorption is discussed as well.