Experimental studies on kaonic atoms at DAΦNE Original Research Article

With precise X-ray spectroscopy on kaonic hydrogen at the DAΦNE electron-positron collider at Laboratori Natzionali di Frascati the chiral symmetry breaking scenario in the strangeness sector will be investigated by studying the K−p and K−d s-wave interaction at threshold. The strong interaction induced shift and width of the kaonic hydrogen 1s atomic state was measured with DEAR (DAΦNE Exotic Atom Research) and in future with SIDDHARTA (Silicon Drift Detector for Hadronic Atom Research with Timing Application) the kaonic hydrogen system will be measured with utmost precision. In addition, data for the K−d system will become available for the first time. Kaonic hydrogen together with precision measurements of kaonic helium will allow the study of the sub-threshold Λ(1405) resonance, which might act as a doorway for the formation of antikaon-mediated deeply bound nuclear states in light nuclei. Therefore, these precision measurements are a powerful tool to test chiral symmetry breaking in systems with strangeness.