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arXiv · 0910.3315

Delta electromagnetic form factors and quark transverse charge densities from lattice QCD

C. Alexandrou·T. Korzec·G. Koutsou·C. Lorcé·V. Pascalutsa·M. Vanderhaeghen·J. W. Negele·A. Tsapalis
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Abstract

We discuss the techniques to extract the electromagnetic Delta form factors in Lattice QCD. We evaluate these form factors using dynamical fermions with smallest pion mass of about 350 MeV. We pay particular attention to the extraction of the electric quadrupole form factor that signals a deformation of the Delta. The magnetic moment of the $Δ$ is extrapolated using a chiral effective field theory. Using the form factors we evaluate the transverse density distributions in the infinite momentum frame showing deformation in the Delta.

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C. Alexandrou, T. Korzec, G. Koutsou, C. Lorcé, V. Pascalutsa, M. Vanderhaeghen, J. W. Negele, A. Tsapalis. 2009-10-17. Delta electromagnetic form factors and quark transverse charge densities from lattice QCD. https://arxiv.org/abs/0910.3315

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