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Title: Search for {theta}{sup ++} Pentaquarks in the Exclusive Reaction {gamma}p{yields}K{sup +}K{sup -}p

Journal Article · · Physical Review Letters
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  1. Rensselaer Polytechnic Institute, Troy, New York 12180-3590 (United States)
  2. Istituto Nazionale di Fisica Nucleare, Sezione di Genova, and Dipartimento di Fisica, Universita di Genova, 16146 Genova (Italy)
  3. Thomas Jefferson National Accelerator Facility, Newport News, Virginia 23606 (United States)

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

OSTI ID:
20860779
Journal Information:
Physical Review Letters, Vol. 97, Issue 10; Other Information: DOI: 10.1103/PhysRevLett.97.102001; (c) 2006 The American Physical Society; Country of input: International Atomic Energy Agency (IAEA); ISSN 0031-9007
Country of Publication:
United States
Language:
English