Evidence of the Θ^+ in the γd \to K^+K^-pn reaction

Abstract

The γd \to K^+K^-pn reaction has been studied to search for the evidence of the Θ^+ by detecting K^+K^- pairs at forward angles. The Fermi-motion corrected nK^+ invariant mass distribution shows a narrow peak at 1.524 +- 0.002 + 0.003 GeV/c^2. The statistical significance of the peak calculated from a shape analysis is 5.1 σ, and the differential cross-section for the γn \to K^- Θ^+ reaction is estimated to be 12 +- 2 nb/sr in the photon energy range from 2.0 GeV to 2.4 GeV in the LEPS angular range by assuming the isotropic production of the Θ^+ in the γn center-of-mass system. The obtained results support the existence of the Θ^+.

arXiv comment31 pages, 16 figures, and 1 table. Submitted to Phys. Rev. C

References in corpus (30)

• Evidence for Narrow S=+1 Baryon Resonance in Photo-production from Neutron
• Exotic Anti-Decuplet of Baryons: Prediction from Chiral Solitons
• Observation of an Exotic $S=+1$ Baryon in Exclusive Photoproduction from the Deuteron
• Observation of a baryon resonance with positive strangeness in K+ collisions with Xe nuclei
• Evidence for the positive-strangeness pentaquark ${\Theta }^{+}$ in photoproduction with the SAPHIR detector at ELSA
• Observation of an Exotic Baryon with S=+1 in Photoproduction from the Proton
• Evidence for a narrow |S|=1 baryon state at a mass of 1528 MeV in quasi-real photoproduction
• Evidence for a narrow baryonic state decaying to K0s-p and K0s-pbar in deep inelastic scattering at HERA
• The gamma + p to K+ + Lambda and gamma + p to K+ + Sigma0 reactions at forward angles with photon energies from 1.5 to 2.4 GeV
• Evidence for a narrow resonance at 1530 MeV/c2 in the K0 p - system of the reaction pp --> Sigma+ K0 p from the COSY-TOF experiment
• Evidence for formation of a narrow pKshort resonance with mass near 1533 MeV in neutrino interactions
• Search for the Pentaquark State in $\psi (2S)$ and $J/\psi$ Decays to $K_S^{0}p{K}^{-}\bar{n}$ and $K_S^0\bar{p}{K}^{+}n$
• Search for the ${\Theta }^{+}$ pentaquark in the reaction $\gamma d\to p{K}^{-}{K}^{+}n$
• Limits for the central production of Theta^+ and Xi^{--} pentaquarks in 920 GeV pA collisions
• Search for the ${\Theta }^{+}$ pentaquark in the reactions $\gamma p\to {\bar{K}}^0{K}^{+}n$ and $\gamma p\to {\bar{K}}^0{K}^{0}p$
• Search for Theta(1540)^+ in exclusive proton-induced reaction p+C(N) \to Theta^+ \bar{K}^0 + C(N) at the energy of 70 GeV
• High Statistics Search for the Theta+(1.54) Pentaquark State
• Further evidence for formation of a narrow baryon resonance with positive strangeness in K+ collisions with Xe nuclei
• Pentaquark Searches at CDF
• Search for Theta+ via pi- p --> K- X reaction near production threshold
• Forward coherent $\varphi$-meson photoproduction from deuterons near threshold
• Observation of narrow baryon resonance decaying into $p{K}_s^0$ in pA-interactions at $70GeV/c$ with SVD-2 setup
• Why the Theta+ is seen in some experiments and not in others - a possible explanation
• Improved study of a possible Theta+ production in the pp -> p K0 sigma+ reaction with the COSY-TOF spectrometer
• Search for the Theta(1540)+ pentaquark using kaon secondary interactions at Belle
• Search for Theta+ via K+p -> pi+X reaction with a 1.2 GeV/c K+ beam
• Suppression of Theta^+(J^P=3/2^(+,-)) photoproduction from the proton
• Comment on the ${\Theta }^{+}$-production at high energy
• Theta+ formation in inclusive gamma D -> pK- X
• K*-couplings for the antidecuplet excitation

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