THE SEARCH FOR AND STUDY OF THE STRANGE MULTIBARYON STATES IN SYSTEMS WITH Л HYPERON AND K_s~0 MESON IN pA COLLISION AT MOMENTUM OF 10 GeV/c

摘要

Exotic strange multibaryon states have been observed in the effective mass spectra of ∧π~±, ∧π~+π~-, ∧p, ∧pp, ∧πp, ∧∧ and ∧K_S~0 K_S~0p, K_S~0π~± subsystems. The measured ∧/π~+ ratio for average multiplicities from the pC reaction is equal to (5.3 ± 0.8) • 10~(-2), and it is approximately two times larger than the ∧/π~+ ratio simulated by the FRITIOF model and than that of experimental pp reactions at the same energy. The observed well-known resonances Σ~(*+) (1385) and K~(*±)(892) from PDG are good tests of this method. The mean value of the mass for the Σ~(*-)(1385) resonance is shifted to 1370 MeV/c~2 and the width is two times larger than the same value from PDG. Such kind of behavior for the width and invariant mass of the Σ~(*-)(1385) resonance is interpreted as an extensive contribution from stopped Θ~-→Aπ~- and medium effect. There is enhancement of the production contribution for all observed hyperons. A few events were registered by hypothesis of light H~0 and heavy H~(0,+) dihyperons. Dihyperons were observed by weak decay channels: (Σ~-p), (∧pπ~-), (∧pπ~0), and (K~-pp).