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arXiv · 1006.0558

The electromagnetic form factors of the Omega in lattice QCD

C. Alexandrou·T. Korzec·G. Koutsou·J. W. Negele·Y. Proestos
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Abstract

We present results on the Omega baryon electromagnetic form factors using $N_f=2+1$ domain-wall fermion configurations for three pion masses in the range of about 350 to 300 MeV. We compare results obtained using domain wall fermions with those of a mixed-action (hybrid) approach, which combine domain wall valence quarks on staggered sea quarks, for a pion mass of about 350 MeV. We pay particular attention in the evaluation of the subdominant electric quadrupole form factor to sufficient accuracy to exclude a zero value, by constructing a sequential source that isolates it from the dominant form factors. The $Ω^-$ magnetic moment, $μ_{Ω^{-}}$, the electric charge and magnetic radius, $\langle r^{2}_{E0/M1} \rangle$, are extracted for these pion masses. The electric quadrupole moment is determined for the first time using dynamical quarks.

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C. Alexandrou, T. Korzec, G. Koutsou, J. W. Negele, Y. Proestos. 2010-06-03. The electromagnetic form factors of the Omega in lattice QCD. https://doi.org/10.1103/physrevd.82.034504

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