An Experimental Review of the ${\Theta }^{+}$ Pentaquark

Abstract

Evidence for the ${\Theta }^{+}$ pentaquark is still sketchy at the present time. This state, if it exists, has a small width and consequently a small production cross section. No single experiment has overwhelming evidence for the ${\Theta }^{+}$ and some non-observations of the ${\Theta }^{+}$ are difficult to understand unless this exotic baryon also has an exotic production mechanism. However, new data from the LEPS and CLAS collaborations with higher statistics are on the way, which will likely resolve the question of whether the ${\Theta }^{+}$ exists.

arXiv comment9 pages and 5 figures. Plenary talk given at the Topical Group on Hadron Physics (Fermilab, Oct. 24-26, 2004)

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Cited by in corpus (12)

• The Hadronic Final State at HERA
• Exotic Tetraquark ud bar[s] bar[s] of J^P=0^+ in the QCD Sum Rule
• Bound State versus Collective Coordinate Approaches in Chiral Soliton Models and the Width of the ${\Theta }^{+}$ Pentaquark
• Study of $Thet{a}^{+}(udud\bar{s})$ in lattice QCD with exact chiral symmetry
• $\Lambda (1520)$ and $\Sigma (1385)$ in the nuclear medium
• Spin 3/2 Pentaquark Resonance Signature in Lattice QCD
• Search for a narrow baryonic state decaying to $p{K}_S^0$ and $\bar{p}{K}_S^0$ in deep inelastic scattering at HERA
• New Particles from Belle
• Theoretical Overview: The New Mesons
• Looking for pentaquarks in Lattice QCD
• Effective mass and decay of ${\Theta }^{+}$ in nuclear matter in quark-meson coupling model
• Resonance radiative decays as a tool for its parity determination