Observation of [formula omitted] Narrow Resonances in the System [formula omitted

Abstract

Experimental data from the 2m propane bubble chamber have been analyzed to search for an exotic baryon state, the Θ + -baryon, in the p K s 0 decay mode for the reaction p+C3H8 at 10 GeV/c. The p K s 0 invariant mass spectrum shows resonant structures with M K s 0 p = 1540 ± 8 , 1613±10, 1821±11 MeV/c2 and Γ K s 0 p = 9.2 ± 1.8 , 16.1 ± 4.1 , 28.0 ± 9.4 MeV/c2. The statistical significance of these peaks has been estimated as 5.5, 4.8 and 5.0 s.d., respectively. There are also small peaks in mass regions of 1690( 3.6 s.d.) and 1980(3.0 s.d.) MeV/c2. The investigation has been performed at the Veksler and Baldin Laboratory of High Energies, JINR.