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تسجيل مستخدم جديدFirst measurement of coherent $phi$-meson photoproduction on deuteron at low energies
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The cross section and decay angular distributions for the coherent phi meson photoproduction on the deuteron have been measured for the first time up to a squared four-momentum transfer t =(p_{gamma}-p_{phi})^2 =-2 GeV^2/c^2, using the CLAS detector at the Thomas Jefferson National Accelerator Facility. The cross sections are compared with predictions from a re-scattering model. In a framework of vector meson dominance, the data are consistent with the total phi-N cross section sigma_{phi N} at about 10 mb. If vector meson dominance is violated, a larger sigma_{phi N} is possible by introducing larger t-slope for the phi N to phi N process than that for the gamma N to phi N process. The decay angular distributions of the phi are consistent with helicity conservation.
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