Related papers: Strangeness plus-one ($S=+1$) resonance-state $P^{…
An enhanced production of strange particles per pion in heavy ion collisions compared to elementary p+p interactions was observed in Pb+Pb reactions at the CERN SPS. New results obtained on small colliding systems, C+C and Si+Si, also show…
Experimental data from the 2m propane bubble chamber have been analyzed to search for an exotic baryon states, in the $\Lambda K^0_s$ decay mode for the reaction p+$C_3H_8$ at 10 GeV/c. The invariant mass spectrum $\Lambda K^0_s$ observe a…
An effective-Lagrangian framework for K Sigma photoproduction from the proton is presented. The proposed model is applicable at forward kaon angles and photon lab energies from threshold up to 16 GeV. The high-energy part of the…
We have continued our investigation of the charge-exchange reaction K^+ Xe --> K^0 p Xe' in the bubble chamber DIANA. In agreement with our previous results based on part of the present statistics, formation of a narrow p K^0 resonance with…
We investigate double-strangeness exchange reactions, $K^-p\to K^+\Xi^-$ and $K^-p\to K^0\Xi^0$, using an effective Lagrangian approach based on a hybrid Regge-plus-resonance model involving rescattering diagrams. We consider the background…
Data on mean numbers of $\Lambda$, $\bar\Lambda$, K's and on the total number $<s\bar s>$ of pairs of strange valence quarks in final state hadrons in hadronic and nuclear collisions at CERN- SPS energies are studied as a function of the…
A Bayesian analysis of the world's $p(\gamma,K^+)\Lambda$ data is presented. We adopt a Regge-plus-resonance framework featuring consistent interactions for nucleon resonances up to spin $J = 5/2$. The power of the momentum dependence of…
Experimental data from the 2m propane bubble chamber have been analyzed to search for an exotic baryon states, in the $K_s^0 p$, $K_s^0 \Lambda$ and $\Lambda p$ decay mode for the reaction p+$C_3H_8$ at 10 GeV/c. The invariant mass spectrum…
The COoler SYnchrotron COSY-J\"ulich delivers phase-space cooled, polarized proton and deuteron beams with momenta up to p=3.65 GeV/c. Various experiments on hadron-induced strangeness production on proton, neutron and nuclear targets have…
We use the $1/N_c$ expansion of QCD to analyse the spectrum of positive parity resonances with strangeness $S = 0, -1, -2$ and -3 in the 2--3 GeV mass region, supposed to belong to the $[\textbf{56},4^+]$ multiplet. The mass operator is…
The mechanism for the formation of the $\Lambda(1405)$ resonance is studied in a chiral quark model that includes quark-meson as well as contact (four point) interactions. The negative-parity $S$-wave scattering amplitudes for strangeness…
We study the $N \pi K$ system in order to investigate the possibility of existence of strangeness +1 resonance(s). The formalism consists of solving the Faddeev equations with the $N \pi$, $\pi K $ and $K N$ $t$-matrices obtained from…
The production of K+ and K- mesons below and at the NN threshold is summarized, based on a comparison of data with transport model calculations. K+ mesons are created in associate production together with hyperons (e.g. Lambda) in…
NA61/SHINE is a fixed target experiment at the CERN Super-Proton- Synchrotron. The main goals of the experiment are to discover the critical point of strongly interacting matter and to study the properties of the onset of deconfinement. In…
In this talk I show recent results on how many excited baryon resonances appear as systems of one meson and one baryon, or two mesons and one baryon, with the mesons being either pseudoscalar or vectors. Connection with experiment is made…
The NA44 Collaboration has measured yields and differential distributions of K+, K-, pi+, pi- in transverse kinetic energy and rapidity, around the center-of-mass rapidity in 158 A GeV/c Pb+Pb collisions at the CERN SPS. A considerable…
The reaction $\gamma p \to pK^+K^-$ was studied at Jefferson Lab with photon energies from 1.8 to 3.8 GeV using a tagged photon beam. The goal was to search for a $\Theta^{++}$ pentaquark, a narrow doubly charged baryon state having…
We study meson-baryon scattering with strangeness -1 in unitary chiral perturbation theory. Ten coupled channels are considered in our work, namely $\pi^0 \Lambda$, $\pi^0 \Sigma^0$, $\pi^- \Sigma^+$, $\pi^+ \Sigma^-$, $K^- p$, $\bar{K}^0…
The reaction $\gamma p\to K^+\Lambda$ has been investigated over the center-of-momentum energy, $W$, range from threshold up to 2.2 GeV in a tree-level effective Lagrangian model that incorporates most of the well-established baryon…
Nuclear experiments near and below the threshold of hyperon production have shown that the production of Kaons is a sensitive probe for the dense QCD equation of state. At beam energies up to 1.5AGeV, strangeness production can probe the…