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تسجيل مستخدم جديدN to Delta electromagnetic transition form factors from Lattice QCD
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C. Alexandrou
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The magnetic dipole, the electric quadrupole and the Coulomb quadrupole amplitudes for the transition $gamma Nto Delta$ are evaluated both in quenched lattice QCD at $beta=6.0$ and using two dynamical Wilson fermions simulated at $beta=5.6$. The dipole transition form factor is accurately determined at several values of momentum transfer. On the lattices studied in this work, the electric quadrupole amplitude is found to be non-zero yielding a negative value for the ratio, $ R_{EM}$, of electric quadrupole to magnetic dipole amplitudes at three values of momentum transfer.
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