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arXiv · hep-lat/0307018

N to Delta electromagnetic transition form factors from Lattice QCD

C. Alexandrou·Ph. de Forcrand·Th. Lippert·H. Neff·J. W. Negele·K. Schilling·W. Schroers·A. Tsapalis
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Abstract

The magnetic dipole, the electric quadrupole and the Coulomb quadrupole amplitudes for the transition $γN\to Δ$ are evaluated both in quenched lattice QCD at $β=6.0$ and using two dynamical Wilson fermions simulated at $β=5.6$. 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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C. Alexandrou, Ph. de Forcrand, Th. Lippert, H. Neff, J. W. Negele, K. Schilling, W. Schroers, A. Tsapalis. 2004-04-03. N to Delta electromagnetic transition form factors from Lattice QCD. https://doi.org/10.1103/physrevd.69.114506

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