Speaker
Mr
Kristian Piscicchia
(LNF)
Description
The AMADEUS experiment deals with the investigation of the low-energy
kaon-nuclei hadronic interaction at the DA$\Phi$NE collider at LNF-INFN, which is fundamental to solve longstanding questions in the non-perturbative strangeness QCD sector. AMADEUS step 0 consisted in the reanalysis of 2004/2005 KLOE data, exploiting $K^-$ absorptions in $H$, ${}^4He$, ${}^{9}Be$ and ${}^{12}C$, leading to the first invariant mass spectroscopy study with in-flight negative kaons. With AMADEUS step 1 a dedicated pure Carbon target was implemented in the central region of the KLOE detector, providing a high statistic sample of pure at-rest $K^-$ nuclear interaction.
We will show the results obtained in the analysis of the $\Sigma^+ \pi^-$ and $\Sigma^0 \pi^0$ (pure isospin 0) channels, intended to shed light on the controversial nature of the $\Lambda(1405)$ state. The analysis of the $\Lambda (\Sigma^0) \pi^-$ channel, from which the measurement of the module of the isospin 1, S-wave non resonant transition amplitude ca be extracted for the first time, will be presented.