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تسجيل مستخدم جديدMeasurements of the photon induced production of $Lambda$ in the $^2$H$({gamma},{Lambda})$X process at threshold energies
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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.
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A study of the $^2$H$({gamma},{Lambda})$X reaction was performed using a tagged photon beam at the Research Center for Electron Photon Science (ELPH), Tohoku University. The photoproduced $Lambda$ was measured in the $p{pi^{-}}$ decay channel by the
upgraded Neutral Kaon Spectrometer (NKS2+). The momentum integrated differential cross section was determined as a function of the scatting angle of ${Lambda}$ in the laboratory frame for five energy bins. Our results indicated a peak in the cross section at angles smaller than cos$theta^{LAB}_{Lambda}$ = $0.96$. The experimentally obtained angular distributions were compared to isobar models, Kaon-Maid (KM) and Saclay-Lyon A (SLA), in addition to the composite Regge-plus-resonance (RPR) model. Both SLA(r$K_{1}K_{gamma}$ = $-1.4$) and RPR describe the data quite well in contrast to the KM model, which substantially under predicted the cross section at the most forward angles. With the anticipated finalized data on ${Lambda}$ integrated and momentum dependent differential cross sections of $^2$H$({gamma},{Lambda})$X~cite{Kaneta_Beckford}, we present our findings on the angular distributions in this report.
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