Unprecedented studies of the low-energy negatively charged kaons interactions in nuclear matter by Amadeus

The AMADEUS experiment aims to provide unique quality data of K− hadronic interactions in light nuclear targets, in order to solve fundamental open questions in the non-perturbative strangeness QCD sector, like the controversial nature of the Λ(1405) state, the yield of hyperon formation below threshold, the yield and shape of multi-nucleon K− absorption, processes which are intimately connected to the possible existence of exotic antikaon multi-nucleon clusters. AMADEUS takes advantage of the DAΦNE collider, which provides a unique source of monochromatic low-momentum kaons and exploits the KLOE detector as an active target, in order to obtain excellent acceptance and resolution data for K− nuclear capture on H, 4He, 9Be and 12C, both at-rest and in-flight. During the second half of 2012, a successful data taking was performed with a dedicated pure carbon target implemented in the central region of KLOE, providing a high statistic sample of pure at-rest K− nuclear interactions. For the future, dedicated setups involving cryogenic gaseous targets are under preparation