Signature of strange dibaryons in kaon- and photon-induced reactions

Abstract

We examine how the signature of the strange dibaryon resonances shows up in scattering amplitudes and observables of the three-body $\bar{K}NN$-$\pi YN(Y=\Sigma ,\Lambda )$ system on the physical real energy axis. The so-called point method is applied to handle logarithmic singularities that appear in solving the Alt-Grassberger-Sandhas equations for the real scattering energies. By taking two different kinds of models for the two-body $\bar{K}N$-$\pi \Sigma$ subsystem, both of which reproduce the available data equally well but give quite a different resonance-pole structure for $\Lambda (1405)$, we also investigate whether the strange-dibaryon production reactions can be used for disentangling the nature of $\Lambda (1405)$.

Comments: 28 pages, 15 figures