[en] We perform a helicity amplitude analysis for the processes of $e^{+}{e}^{-}\to J/\psi ,\psi (2S)\to \mathrm{\Xi }(1530)\overline{\mathrm{\Xi }}(1530)\to \pi \pi \mathrm{\Xi }\overline{\mathrm{\Xi }}\to 4\pi \mathrm{\Lambda }\overline{\mathrm{\Lambda }}\to 6\pi p\overline{p}$. The joint angular distribution for these processes are obtained, which allows a proper estimation of the detection efficiency using helicity amplitude information. In addition, the sensitivities of measurement of hyperon asymmetry decay parameters for these processes are discussed.

[en] With 4.36x10⁶ events, spin precession in a magnetic field has been used to measure the magnetic moment of the Ξ^- hyperon as -0.6505±0.0025 nuclear magnetons

[en] Experimental results of a search for the Ξ_3/2(1860) cascade pentaquark state in data collected with the CDF 2 Detector in Run II at the Tevatron are presented. No evidence for these states in the neutral Ξ^-π⁺ and doubly charged Ξ^-π^- modes has been found. Preliminary upper limits on yields at 1862 MeV/c² relative to the well established resonance Ξ*(1530)⁰ are presented

[en] With experimental data of ^p annihilation at rest on nuclei of ⁴He, collected by the Obelix spectrometer (LEAR, CERN), we have studied a number of reactions with 4 and 5 charged particles in the final state, distinguishing the annihilations on more than one nucleon, and with strangeness production. The main results of our observations are: (a) a higher (up to 20 times) strangeness production in ⁴He than in H; (b) the evidence of a possible signature of a K_pp (K_ppn) bound state; (c) a measurement of a double strangeness production (2K⁺) and a hint for some production yields of double-strangebound systems like 2K ^-2n; (d) a signal compatible with the baryonic Θ(1530) resonance, interpreted as a pentaquark system. Presented at the 20th Few-Body Conference, Pisa, Italy, 10-14 September 2007. (author)

[en] The QCD sum-rule technique is used to study the properties of the leading-twist wave functions of the Σ*(1385) and Ξ*(1530) hyperons. Model wave functions are proposed which satisfy the QCD sum roles. These wave functions are used to calculate the electromagnetic form factors of the Σ* and Ξ* resonances and the form factors for octet---decuplet transitions

[en] A method is presented for analysis of correlation function of two nonidentical particles with strong and Coulomb interactions, resonance formation, channel coupling, and spin structure. For resonance reactions we derive a formula giving the small distance contribution to the correlation function. The formalism is used to analyze the preliminary Relativistic Heavy Ion Collider data on π^±Ξ^± correlation measurements. The Ξ^*(1530) resonance is successfully described. The πΞ source size is obtained.

[en] We study pentaquark Θ⁺(I=0, J=1/2) in the QCD sum rules emphasizing that we cannot extract any properties of the pentaquark outside of the Borel window. To find the appropriate Borel window, we prepare a favorable set up of the correlators and carry out the operator product expansion up to dimension 15 within factorization hypothesis. Our procedures reduce the unwanted high energy contaminations and enhance the low energy correlation. In the Borel window, independent analyses for the chiral-even and odd sum rules give the consistent values of the Θ⁺ mass, 1.68±0.22 GeV, and the residue. The parity is found to be positive. (author)

[en] Photoproduction of the cascade resonances has been investigated in the reactions γp → K⁺K⁺(X) and γp → K⁺K⁺π^-(X). The mass split of the Ξ doublet is measured to be 5.4 ± 1.8 MeV/c², consistent with existing measurements. The differential (total) cross sections for the Ξ^- have been determined for photon beam energies from 2.75 to 3.85 (4.75) GeV, and are consistent with a possible production mechanism of Y* → K⁺Ξ^- through a t-channel process. The reaction γp → K⁺K⁺π^-(Ξ⁰) has also been investigated in search of excited cascade resonances. No significant signal of excited cascade states other than the Ξ^-(1530) is observed. The cross section results of the Ξ^-(1530) have also been obtained for photon beam energies from 3.35 to 4.75 GeV

[en] A procedure is presented to calculate the partial and total conversion widths of Ξ hypernuclear states produced in the (K^-,K⁺) reaction on typical targets (¹²C and ¹⁶O). The final state after the Ξ^-p→ΛΛ conversion is classified into three types according to the bound and/or continuum two Λ's: double-Λ sticking, single-Λ sticking, and no sticking. The probabilities leading to these final states are evaluated as a function of the Ξ-nucleus potential depth V₀^Ξ. A possible final state with a neutron emission is also considered. It is confirmed that the interaction between the Ξ particle and a proton in the deep 0s orbit plays an important role to bring about the double-Λ sticking. The calculation shows that the double-Λ and single-Λ sticking probabilities are sensitive to the strength of V₀^Ξ, which suggests that the observation of these probabilities provides us with a useful indicator for Ξ^- hypernuclear bound states

[en] The short-lived resonances have been used to study properties of the heavy-ion collisions at SPS, RHIC and the LHC. The resonance yields measured in the hadronic decay channels are affected by the rescattering and regeneration effects in the late hadronic phase. The mesonic and baryonic resonances with different strangeness content are used to study the strangeness enhancement phenomenon predicted as one of the signatures for the QCD phase transition. Having different masses and baryonic numbers, the resonances contribute to the study of hadronization mechanisms at low and intermediate transverse momenta. The extensive resonance measurements are not experimentally available in heavy-ion collisions at NICA energies. In this contribution, we study the resonance properties and their sensitivity to different stages of Au+Au collisions at $\sqrt{s_{NN}}$= 4–11 GeV. Results of feasibility studies for reconstruction of ρ(770)⁰, K*(892), ϕ(1020), Λ(1520), Σ(1385)^± and Ξ(1530)⁰ resonances in the MPD detector at NICA are presented and discussed. (paper)