Search for the {theta}{sup +} Pentaquark in the Reaction {gamma}d{yields}pK{sup 0}K{sup -}(p) with CLAS

Journal Article · Fri Oct 26 04:00:00 EDT 2007 · AIP Conference Proceedings

DOI:https://doi.org/10.1063/1.2813796· OSTI ID:21036022

Baltzell, Nathan A ^[1]

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1. University of South Carolina, Columbia, South Carolina 29208 (United States)

A search for photo-production of the {theta}{sup +}(1540) pentaquark and its decay to pK{sup 0} was performed with the CLAS detector system at Jefferson Lab. In the exclusive channel {gamma}d{yields}pK{sup 0}{sub s}K{sup -}(p), about twenty-thousand events with a slow missing proton, {pi}{sup +}{pi}{sup -} decay of the neutral kaon, and photon energy between 1.6 and 3.6 GeV are fully reconstructed. Included are numerous hyperon and meson resonances, with their decays to pK{sup -} and K{sup 0}K{sup -} respectively. To understand the possibility of a pentaquark signal amidst the backgrounds, a phenomenological isobar-inspired model of complex Breit-Wigner amplitudes and decay angular distributions for the resonances is fit to the data with a maximum likelihood method. No pentaquark signal is found above the background. The upper limit on the total production cross section is measured to be consistent with other channels published by the collaboration, but systematic studies are still in progress.

• OSTI ID: 21036022
• Journal Information: AIP Conference Proceedings, Journal Name: AIP Conference Proceedings Journal Issue: 1 Vol. 947; ISSN APCPCS; ISSN 0094-243X
• Country of Publication: United States
• Language: English

Related Subjects

72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS
ANGULAR DISTRIBUTION
BREIT-WIGNER FORMULA
CEBAF ACCELERATOR
CROSS SECTIONS
GEV RANGE
HYPERONS
KAONS NEUTRAL
MASS SPECTRA
MAXIMUM-LIKELIHOOD FIT
PARTICLE DECAY
PARTICLE IDENTIFICATION
PHOTONS
PHOTONUCLEAR REACTIONS
PHOTOPRODUCTION
PIONS MINUS
PIONS PLUS
PROTONS
QUANTUM CHROMODYNAMICS
QUARK MODEL
RESONANCE PARTICLES