Publications (4)7.37 Total impact
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Article: Measurements of the photon induced production of $\Lambda$ in the $^2$H$({\gamma},{\Lambda})$X process at threshold energies
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ABSTRACT: An experiment was carried out with the NKS2+ in 2010 at the Research Center for Electron Photon Science (ELPH), in which tagged photon beams in the range of 0.8 $\le$ $E_{\gamma}$ $\le$ 1.1 GeV were impinged on a liquid $^2$H target positioned at the center of the NKS2+. The produced $\Lambda$ was subsequently detected by the $p{\pi^{-}}$ decay channel. Integrated cross sections of the $^2$H$({\gamma},{\Lambda})$X in the angular region of 0.9 $\le$ $\cos{\theta}_{\Lambda}^{LAB}$ $\le$ 1.0 was derived and compared with preceding experimental results of the NKS2 collaboration. In addition, the momentum spectra for two photon energy regions were also procured. The ${\Lambda}$ angle dependent cross sections as a function of the scattering angle in the laboratory system was additionally deduced. We present the latest results on the excitation function of ${\Lambda}$ photoproduction, the momentum distributions, angular distributions, and polarization.10/2012; -
Article: Search for the Θ^{+} Pentaquark via the π^{-}p→K^{-}X Reaction at 1.92 GeV/c.
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ABSTRACT: The Θ^{+} pentaquark baryon was searched for via the π^{-}p→K^{-}X reaction with a missing mass resolution of 1.4 MeV/c^{2} (FWHM) at the Japan Proton Accelerator Research Complex (J-PARC). π^{-} meson beams were incident on the liquid hydrogen target with a beam momentum of 1.92 GeV/c. No peak structure corresponding to the Θ^{+} mass was observed. The upper limit of the production cross section averaged over the scattering angle of 2° to 15° in the laboratory frame is obtained to be 0.26 μb/sr in the mass region of 1.51-1.55 GeV/c^{2}. The upper limit of the Θ^{+} decay width is obtained to be 0.72 and 3.1 MeV for J_{Θ}^{P}=1/2^{+} and J_{Θ}^{P}=1/2^{-}, respectively, using the effective Lagrangian approach.Physical Review Letters 09/2012; 109(13):132002. · 7.37 Impact Factor -
Article: Search for the $\Theta^{+}$ pentaquark via the $\pi^-p\to K^-X$ reaction at 1.92 GeV/$c$
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ABSTRACT: The $\Theta^+$ pentaquark baryon was searched for via the $\pi^-p\to K^-X$ reaction in a missing-mass resolution of 1.4 MeV/$c^2$(FWHM) at J-PARC. $\pi^-$ meson beams were incident on the liquid hydrogen target with the beam momentum of 1.92 GeV/$c$. No peak structure corresponding to the $\Theta^+$ mass was observed. The upper limit of the production cross section averaged over the scattering angle of 2$^{\circ}$ to 15$^{\circ}$ in the laboratory frame was obtained to be 0.26 $\mu$b/sr in the mass region of 1.51$-$1.55 GeV/$c^2$.The upper limit of the $\Theta^+$ decay width using the effective Lagrangian approach was obtained to be 0.72 MeV/$c^2$ and 3.1 MeV/$c^2$ for $J^P_{\Theta}=1/2^+$ and $J^P_{\Theta}=1/2^-$, respectively.03/2012; -
Article: Report on strangeness photoproduction experiments performed with the Neutral Kaon Spectrometer 2
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ABSTRACT: An experiment designed to investigate the strangeness photoproduction process using a tagged photon beam in the energy range of 0.90 -1.08 GeV incident on a liquid deuterium target was successfully performed. The purpose of the experiment was to measure the production of neutral kaons and the lambda particles on a deuteron. The generation of photo produced particles was verified by the measurement of their decayed charged particles in the Neutral Kaon Spectrometer 2. The reconstructed invariant mass distributions were achieved by selecting events where two or more particles tracks were identified. Preliminary results are presented here.02/2012;
