The reaction gamma p -> 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 strangeness S=+1 and isospin I=1, in the pK(+) invariant mass spectrum. No statistically significant evidence of a Theta(++) was found. Upper limits on the total and differential cross section for the reaction gamma p -> K-Theta(++) were obtained in the mass range from 1.5 to 2.0 GeV/c(2), with an upper limit for a narrow resonance with a mass M-Theta(++)=1.54 GeV/c(2) of about 0.15 nb, 95% C.L.. This result places a stringent upper limit on the Theta(++) width Gamma(++)(Theta)< 0.1 MeV/c(2).

Search for Theta(++) Pentaquarks in the Exclusive Reaction gamma p -> K(+)K(-)p

RICCO, GIOVANNI;TAIUTI, MAURO GINO;
2006-01-01

Abstract

The reaction gamma p -> 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 strangeness S=+1 and isospin I=1, in the pK(+) invariant mass spectrum. No statistically significant evidence of a Theta(++) was found. Upper limits on the total and differential cross section for the reaction gamma p -> K-Theta(++) were obtained in the mass range from 1.5 to 2.0 GeV/c(2), with an upper limit for a narrow resonance with a mass M-Theta(++)=1.54 GeV/c(2) of about 0.15 nb, 95% C.L.. This result places a stringent upper limit on the Theta(++) width Gamma(++)(Theta)< 0.1 MeV/c(2).
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Utilizza questo identificativo per citare o creare un link a questo documento: https://hdl.handle.net/11567/301681
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