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تسجيل مستخدم جديدDifferential Cross Section Measurements for $gamma ntopi^-p$ Above the First Nucleon Resonance Region
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The quasi-free $gamma dtopi^{-}p(p)$ differential cross section has been measured with CLAS at photon beam energies $E_gamma$ from 0.445 GeV to 2.510 GeV (corresponding to $W$ from 1.311 GeV to 2.366 GeV) for pion center-of-mass angles $costheta_pi^{c.m.}$ from -0.72 to 0.92. A correction for final state interactions has been applied to this data to extract the $gamma ntopi^-p$ differential cross sections. These cross sections are quoted in 8428 $(E_gamma,costheta_pi^{c.m.})$ bins, a factor of nearly three increase in the world statistics for this channel in this kinematic range. These new data help to constrain coupled-channel analysis fits used to disentangle the spectrum of $N^*$ resonances and extract their properties. Selected photon decay amplitudes $N^* to gamma n$ at the resonance poles are determined for the first time and are reported here.
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