2004/07/14 by SPHINX Collaboration, The SPHINX Collaboration, Yu. M. Antipov +20
Physics and Astronomy · #Bar (unit) #Baryon #Energy (signal processing) #High-Energy Particle Collisions Research #Lambda #Nuclear physics #Nucleon #Order (exchange) #Particle physics #Particle physics theoretical and experimental studies #Pentaquark #Physics #Production (economics) #Proton #Quantum Chromodynamics and Particle Interactions #Quantum mechanics #Strangeness #hep-ex
paper · pdf · doi:10.1140/epja/i2004-10062-4
published as Eur.Phys.J.A21:455-468,2004 · 14 pages; 16 figures. Based on talks given by V.F.Kurshetsov at the IHEP seminar (Protvino, IHEP, February 5, 2004) and at the session of Nuclear Department of Russian Academy of Science (Moscow, ITEP, March 5, 2004)
arxiv created 2004/07/14 · openalex publication_date 2004/09/01 · arxiv updated 2009/12/01 · openalex created_date 2016/06/24 · openalex updated_date 2026/08/05
A search for narrow Theta(1540)+, a candidate for pentaquark baryon with positive strangeness, has been performed in an exclusive proton-induced reaction p+C(N) → Theta+ K0 + C(N) on carbon nuclei or quasifree nucleons at Ebeam=70 GeV (sqrts = 11.5 GeV) studying nK+, pKS and pKL decay channels of Theta(1540)+ in four different final states of the Theta+ K0 system. In order to assess the quality of the identification of the final states with neutron or KL we reconstructed Lambda(1520)→ nKS and phi→ KLKS decays in the calibration reactions p+C(N)→ Lambda(1520)K+ + C(N) and p+C(N)→ pϕ+ C(N). We found no evidence for narrow pentaquark peak in any of the studied final states and decay channels. Assuming that the production characteristics of the Theta+ K0 system are not drastically different from those of the Lambda(1520)K+ and pϕsystems, we established upper limits on the cross section ratios sigma(Theta+K0)/sigma(Lambda(1520)K+) < 0.02 and sigma(Theta+K0)/sigma(pϕ) < 0.15 at 90% CL and a preliminary upper limit for the forward hemisphere cross section sigma(Theta+K0) < 30 nb/nucleon.