Wave functions of the nucleon and its parity partner from lattice QCD

Nikolaus Warkentin; Vladimir M. Braun; Meinulf Göckeler; Thomas Kaltenbrunner; Andreas Schäfer; Gerrit Schierholz; Yoshifumi Nakamura; Dirk Pleiter; Roger Horsley; James M. Zanotti; Paul E. L. Rakow; Hinnerk Stüben

arXiv · 0811.2212

Wave functions of the nucleon and its parity partner from lattice QCD

Nikolaus Warkentin·Vladimir M. Braun·Meinulf Göckeler·Thomas Kaltenbrunner·Andreas Schäfer·Gerrit Schierholz·Yoshifumi Nakamura·Dirk Pleiter·Roger Horsley·James M. Zanotti·Paul E. L. Rakow·Hinnerk Stüben

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Abstract

We compute moments of distribution amplitudes using gauge configurations with two flavors of clover fermions from QCDSF/DIK and operators which are optimized with respect to their behavior under the lattice symmetries. The knowledge of these quantities helps in understanding the internal structure of hadrons and in the analysis of (semi-)exclusive processes. We present results for the nucleon distribution amplitude which suggest that the asymmetries (the deviations from the asymptotic form) are smaller than indicated by sum rule calculations. Using the same approach we were also able to calculate the same quantities for the $N^\star(1535)$, the parity partner of the nucleon. These results show a stronger deviation from the asymptotic form.

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Nikolaus Warkentin, Vladimir M. Braun, Meinulf Göckeler, Thomas Kaltenbrunner, Andreas Schäfer, Gerrit Schierholz, Yoshifumi Nakamura, Dirk Pleiter, Roger Horsley, James M. Zanotti, Paul E. L. Rakow, Hinnerk Stüben. 2008-11-13. Wave functions of the nucleon and its parity partner from lattice QCD. https://arxiv.org/abs/0811.2212

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