Studies of low-energy K- nuclear interactions by AMADEUS

R Del Grande,G Belloti,D Pietreanu,M Iliescu,K Piscicchia,L De Paolis,F Ghio,M Bazzi,S Wycech,M Iwasaki,C Guaraldo,P Levi Sandri,M Silarski,D Bosnar,F Sirghi,H Shi,J Márton ,A M Bragadireanu ,Arslan Dawood Butt ,O Vázquez Doce ,S Okada,E Widmann,M Miliucci ,D Sirghi ,P Moskal,J Zmeskal,M Skurzok,R S Hayano ,C Curceanu,M Cargnelli,A Scordo,A Spallone,C Fiorini,L Fabbietti

doi:10.1051/epjconf/201818202035

Abstract

The goal of the AMADEUS experiment is to shed light on unsolved fundamental issues in the non-perturbative strangeness QCD sector through the study of lowenergy K- hadronic interactions with light nuclear targets. The main open questions are the controversial nature of the Δ(1405) state, which is investigated in hyperon-pion correlation studies, and the possible existence of exotic antikaon multi-nucleon clusters, whose search in K- induced reactions is intimately related to the studies of the K- multi-nucleon absorption processes in hyperon-nucleon/nucleus channels. The DAΦNE collider at the INFN-LNF provides unique monochromatic low-momentum kaons from the φ meson decay almost at-rest, suitable for the AMADEUS studies. The KLOE detector is exploited 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.

Highlights

The AMADEUS (Anti-kaonic Matter At DAΦNE: An Experiment with Unraveling Spectroscopy) [1] collaboration aims to provide unique quality data of low-energy K− hadronic interactions in light nuclei (e.g. H, 4He, 9Be and 12C) in order to afford experimental constraints on the non-perturbativeQCD in the strangeness sector
AMADEUS takes advantage of the low momentum, almost monochromatic, charged kaons provided by the decay of φ mesons at-rest at the DAΦNE factory [2]
Chiral unitary models predict the emerging of two poles contributing to the Λ(1405) line-shape, with a high mass pole strongly coupled to the K N channel [6, 7, 10, 12], whereas the phenomenological potentials models expect the existence of a single pole of the scattering amplitude at 1405 MeV

Summary

Introduction

The AMADEUS (Anti-kaonic Matter At DAΦNE: An Experiment with Unraveling Spectroscopy) [1] collaboration aims to provide unique quality data of low-energy K− hadronic interactions in light nuclei (e.g. H, 4He, 9Be and 12C) in order to afford experimental constraints on the non-perturbative. The non-perturbative chiral SU(3) dynamics [4,5,6,7] and the phenomenological potential approach [8, 9] are the main theoretical tools to overcome the difficulty. In both cases the Kdynamics above threshold is well described because the two models are constrained to the scattering data but the sub-threshold extrapolations are in strong disagreement [10, 11].

The KLOE detector at DAΦNE

Findings

Particle Identification